APreliminaryRevisionoftheNorthAmericanSpeciesofCactus，Anhalonium，andLophophorabyJohnM。Coulter。
U。S。DepartmentofAgricultureDivisionofBotanyCONTRIBUTIONSFROMTHEU。S。NATIONALHERBARIUM
Vol。III——No。2
IssuedJune10，1894
PreliminaryRevisionoftheNorthAmericanSpeciesofCactus，Anhalonium，andLophophora。
byJohnM。Coulter。
PublishedbyAuthorityoftheSecretaryofAgricultureWashingtonGovernmentPrintingOffice1894
LETTEROFTRANSMITTAL
U。S。DepartmentofAgricultureDivisionofBotanyWashington，D。C。，March21，1894
SIR：Ihavethehonortotransmitherewith，forpublicationasVol。III，No。2，ofContributionsfromtheU。S。NationalHerbarium，aPreliminaryRevisionoftheNorthAmericanspeciesofCactus，Anhalonium，andLophophora，byPresidentJohnM。
Coulter。
Respectfully，FrederickV。Coville，ChiefoftheDivisionofBotany。
Hon。J。SterlingMorton，SecretaryofAgriculture。
PRELIMINARYREVISIONOFTHENORTHAMERICANSPECIES
OFCACTUS，ANHALONIUM，ANDLOPHOPHORA。
PrefatoryNote。
Inthefallof1890Dr。GeorgeVasey，thenBotanistoftheDepartmentofAgriculture，arrangedwithmetopreparearevisionofNorthAmericanCactaceae。Owingtothepeculiardifficultyofpreservingmaterialthefamilywaspoorlyrepresented，eveninourleadingherbaria。TosecurealargeamountofadditionalmaterialinthewayofspecimensandfieldnotestheDepartmentauthorizedmetovisittheregionoftheMexicanboundaryduringthesummerof1891。PreliminarytothisexplorationitwasnecessarytoexaminetheEngelmanncollectionofCactaceae，inthepossessionoftheMissouriBotanicalGarden。Thiscollection，supplementedbythecontinualadditionsmadeatthegarden，isbyfarthelargestcollectionofskeletonsandlivingspecimensinthiscountry，andalsocontainsthelargemajorityofourtypes。
InMarch，1891，Ivisitedthiscollectionandmadesuchnotesasseemednecessaryforuseinthefield，andinJune，accompaniedbyMr。W。H。EvansandMr。G。C。Nealley，IbeganfieldworkintheneighborhoodofElPaso，Tex。AftertendaysofexplorationitwasnecessaryformetoleavethefieldworkinchargeofMr。
Evans，who，withMr。Nealley，continuedworkwestward，duringJulyandapartofAugust，tosouthernCalifornia，alongtheSouthernPacificRailway。Asaresultalargenumberofcompleteplantbodieswassecured，butveryfewofthemwereinflowerandthefieldnotesindicatedlittlebesidescollectionstations。
DuringthefollowingfallandwinterpreliminarydeterminationsofthismaterialweremadebyMr。Evans。
Inthefallof1892criticalstudyofthisandothercollectionswasbeguninconnectionwithmyassistants，Dr。ElmonM。FisherandMr。EdwinB。Uline，whohaveeversincerenderedconstantandmostimportassistanceintheexaminationofmaterialandbibliography，whichalonehasmadetheworkpossibleinthemidstofotherpressingduties。
Inthespringof1893thesetwogentlemenspentseveralweeksattheMissouriBotanicalGardeninthecriticalstudyofitsrichmaterial，andduringthelatterpartoftheirstayIassistedinthework。Dr。WilliamTrelease，thedirectorofthegarden，hadhastenedthearrangementoftheEngelmannmaterial，andhadmountedinconvenientformthelargemassofnotesleftbyDr。
Engelmann。Thesenotescontainednotonlycriticalremarksuponknownspecies，butalsothediagnosesofmanyunpublishedspecieswhichhadcomeintohishands，notablythosecollectedbyMr。
WilliamGabbin1867inLowerCalifornia。Thecollectionsthathavethusfarbeenstudiedare：
（1）ThoseoftheMissouriBotanicalGarden；andthanksareespeciallyduetoDr。Treleaseforhisgenerouscooperationintheuseofthismaterial，withoutwhichtheworkwouldhavebeenimpossible。
（2）ThoseoftheDepartmentofAgriculture，includingtheresultsofseveralrecentexplorations，fortheuseofwhichIamindebtedtoMr。FrederickV。Coville。
（3）ThoseoftheGrayHerbariumatHarvardUniversity，whichDr。
B。L。Robinsonkindlyplacedatmydisposal。
（4）ThoseoftheCaliforniaAcademyofSciences，notablyrichinformsfromLowerCaliforniaandtheadjacentislands，kindlyloanedbyMr。T。S。Brandegee。
（5）ThoseofDr。LouisEschanzier，ofSanLuisPotosi，Mexico，whosendalargeseriesofMexicanformscollectedin1891。
（6）Numeroussmallsetsfromdifferentcorrespondents，whohavegivenbothtimeandmaterialinaidingthework。
ItisneedlesstosaythatDr。GeorgeEngelmann，thegreatpioneerstudentofthisdifficultfamily，hasopenedthepathsinwhichwemustfollow，anditwasexceedinglyunfortunatethathewasnotabletocompletethefinalrevisionthathehadinmind。
Thedifficultieswhichbesetthecriticalstudyofthisgroupcannotbeeasilyexaggerated。Suchscantymaterialashasbeencollectedhasbeenforthemostpartveryincomplete，consistingofplantbodieswithoutflowerorfruit，flowerorfruitwithoutplantbodies，andbunchesofspineswithouteither。Thespeciesaredisplayedalsointhemostinaccessibleregions，andtheirculminationisfoundinthestillpoorlyknownregionsofMexico。
Onaccountoftheirsingularformsandoftenbrilliantflowerstheyhavelongbeenextensivelycultivated，especiallyinEurope。
ThesecultivatedformshaveformedthebasisoforiginaldescriptionsinalmostalloftheEuropeanpublications，andinveryrarecaseshaveanytypesbeenpreserved。Asaresult，thebibliographyofCactaceaeisappalling，anditisquestionablewhethersatisfactoryconclusionscanbereachedinthecaseofhundredsofpublishednames。Theearlierdescriptionswerenotonlymeager，butwerebaseduponwhatarenowregardedveryinsufficientcharacters，andintheabsenceoftypesitisnotonlyunsafe，butimpossibletoventureanopinionconcerningtheiridentity。Inviewofthesefacts，Ihavethoughtitadvisabletopresentapreliminaryrevisionoftheorder，whichshallcontaintheresultsofthestudyofmaterialconfessedlyinsufficient。Withsuchknowledgeaswepossessbroughttogether，itishopedthatthestudyofthisveryinterestingandmuchneglectedgroupwillbestimulated，andthatmorecriticalexplorationofoursouthwesternterritoryandadjacentMexicowillmakeamoresatisfactorypresentationpossible。Itwouldbeuselesstonoticethevastnumberofreputedspeciesthatarenotrepresentedbyactualspecimensinourpossession。
Intheproposedpreliminaryaccountofthefamily，ofwhichthepresentpaperisthefirstpart，onlythosegeneraareconsideredwhichformapartofthefloraoftheUnitedStates，andthosespecieswhichIhavebeenabletoexamineandtoidentifywithreasonablecertainty。AllformscreditedtotheUnitedStateshavebeenstudied，andtheaccountofthesespeciesmaybeconsideredfairlycomplete，butthefarmorenumerousMexicanspeciesarebutscantilyrepresented。TheMexicanboundaryissounnaturaladividinglineinthedistributionofCactaceaethatithasbeendisregarded，andallthespeciesstudiedhavebeenarrangedinalinealseriesofuniformprominence。Sofarasknownthesubjectofgeographicaldistributionisconsidered，butitwillbeseenhowmeagerisourknowledgeofthissubject。Itistobehopedthatthispreliminarypresentationwillprovokeexplorationandstudy，andthatspecieswillnotonlybecollected，butallthefactsoftheirdistributionnoted。Itismorethanprobablethatourpresentnotionofspeciesinthisgroupmustbemuchmodified，anddoubtlessmanyformsareatpresentkeptspecificallydistinctwhichwillprovetobebutdifferentphasesofasinglespecies。
Inthematterofgenericdelimitationweareinstillgreateruncertainty，andseveralgenericlinesatpresentrecognizedmustberegardedaspurelyarbitrary，afactwhichmustbecomestillmoreevidentwithadditionalmaterial。Thewholegroupistoberegardedasmadeupofpoorlydifferentiatedformsandonlylongobservationundercultivationcandeterminethepossibilitiesofspecificvariationundertheinfluenceofenvironment，ofage，ofinherenttendencies。Forinstance，thattheseplantschangeinformandinspinecharacterswithincreasingageandaftertheyhavebeguntoflowercannotbedoubted，butwhatdescribedformshavethusbeenseparatedindescriptionscanonlybeguessedat。
JohnM。Coulter。
LakeForestUniversity，LakeForest，Ill。，January，1891。
CACTUS，ANHALONIUM，ANDLOPHOPHORA。
1。CACTUSLinn。Sp。Pl。466（1753），restricted。
MAMILLARIAHaw。Synop。177（1812），notStackh。（1809）。
Usuallyglobosetooblongplants（simple，branchingorcespitose），butsometimesslender-cylindrical，coveredwithspine-bearingtubercles：flower-bearingareolaaxillary（withreferencetotubercles），entirelyseparatefromtheterminalspine-bearingareola，althoughsometimes（Coryphantha）connectedwithitbyawoollygroovealongtheupperfaceofthetubercle：
ovarynaked：seedssmoothorpitted：embryousuallystraight，withshortcotyledons。OriginallydefinedbyLinnaeusinhisSystema，ed。l（1735）。
TheLinnaeangenusCactusof1753included22speciesandwascoextensivewiththepresentorder。In1812thespecieswereseparatedbyHaworthintofivegenera，theoriginalgenericnameCactusbeingdiscarded。AmongthesespeciesC。mamillarisseemstohavestoodasthetype，notonlyoftheLinnaeangenusCactus，butalsoofHaworth’sMamillaria，andassuchshouldretaintheoriginalgenericname。Besides，Mamillariawasusedasthegenericnameofanalgain1809。CactusmamillarisL。istheWestIndianMamillariasimplexHaw。
Fromonepointofviewthetwosectionsofthegenus（EumamillariaandCoryphantha）deservegenericseparation，forthecharacterofgroovelessandgroovedtuberclesseemstoholdwithoutexception，andthesectionsareseparatedwithmorecertaintythanarecertainspeciesofCoryphanthaandEchinocactus。Ifgeneraaresimplygroupsofconveniencetheseparationshouldbemade。
I。EUMAMILLARIA。Flowersfromtheaxilsoftheolderorfull-growntubercles（henceusuallyappearinglateral），mostlysmall，andgenerallyfromwhitishtopinkorred：tuberclesnevergrooved：fruitalmostalwaysclavateandscarlet。
A。Tuberclesmoreorlessquadrangular。
*Centralspinesnothooked。
Morethanonecentralspine。
1。Cactusalternatus，sp。nov。
Subglobose，10cm。indiameter，simple：tubercleslong（15to20
mm。）andspreading，withwoollyaxils：radialspines3，rigidandrecurved，5mm。long；centralspines3，verystoutandmuchrecurved，20to30mm。long，alternatingwiththeradials；allashycoloredandoftentwisted：flowerandfruitunknown。——TypeinHerb。Coulter。
Thefewspines，withtheveryshortradialsalternatingwiththeverylongandstoutcentrals，furnishastrikingcharacter。
Occasionallyoneofthecentralsiswanting。
2。Cactusacanthophlegmus（Lehm。）Kuntze，Rev。Gen。Pl。260
（1891）。
MamillariaacanthophlegmaLehm。Delect。Sem。Hamb。（1833）
Subglobosewithadeeplydepressedvertex，orbecomingcylindrical，3to8。5cm。indiameter：tuberclessharplyquadrangular-conical，withdenselywoollyaxils：radialspines15
to30，white，veryslender（bristly）andradiant，sometimescoarsecapillary，4to7mm。long，interwovenwiththoseofneighboringtuberclesandsocoveringthewholeplant；centralspines2to4，robustandstraight，erectordivergent，whitishorreddish，black-tipped，5to6。5mm。long：flowersreddish，1
to2cm。broad：fruitunknown。Typeunknown。
FromCoahuilaandSanLuisPotositoOaxaca。Fl。May。
Specimensexamined：Coahuila（Poselgerof1856；Pringle3116of1890）：SanLuisPotosi（Eschanzierof1891）。
Thecentralspinesarequitevariableinnumberandarrangement。
Incasetherearetwotheyareverticallyplacedandareeithererectandparallelorwidelydivergent。Eventhreecentralsmayoccurinthesameverticalplane；butmoreusuallythethreeorfourcentralsarearrangedaboutacenterandarewidelydivergent。Thetuberclesareapttopersistandtobecomenakedandcorkywithage。Theaxillarywoolandthecapillaryradialsarealsoapttobemoreorlesspersistent，thusgivingthewholeplantawoollyappearance。
3。Cactusbrandegei，sp。nov。
Cylindrical：tuberclessharplyquadrangular-conical，6to8mm。
long，withdenselywoollyaxils：radialspinesabout10，slenderandrigid，whitishwithduskytips，spreadingbutnotradiant，7
to10mm。long；centralspines3or4，stouterandslightlylonger，erect-spreading（sometimesslightlycurved），reddish-brownbelow，becomingblackishabove：flowerssmall（scarcelylongerthanthetubercle？）：fruitunknown。TypeinHerb。Calif。Acad。
SanJorge，LowerCalifornia。Fl。April。
Specimensexamined：LowerCalifornia（Brandegeeof1889，atSanJorge）。
ThespecieshassomewhatthespinecharactersofC。palmeri，butthesharplyquadrangularandlongertubercleswithaxillarywoolfreefrombristlessuggestaverydifferentaffinity。
4。Cactusdensispinus，sp。nov。
Globose，7。5cm。indiameter，simple：tuberclesshort，withwoollyaxils：radialspinesabout25，erect-spreading，slenderbutrigid，yellow（brownishtoblackwithage），unequal，8to10
mm。long；centralspines6，alittlelonger（10to12mm。）andstraight，morerigidanddarker，black-tipped：seedsobovate，reddish-brown，1mm。long。TypeinHerb。Coulter。
Veryeasilydistinguishedbyitsdense，erectspines，whichsocompletelycovertheplantastogiveittheappearanceofalargechestnutbur。Anothermuchsmallerform，whichseemstobeavariety，hasstouterandlongerashy-whitespines，thecentralsdarker-tipped，andthelowercentralsslightlycurved。
Oneshortcentralspine（rarelytwoornone）：ovariesimmersed：seedssmall，yellowandrugulose：simple。
5。Cactusheyderi（Muhlenpf。）Kuntze，Rev。Gen。Pl。260（1891）。
MamillariaheyderiMuhlenpf。Allg。Gart。Zeit。xvi。20（1848）。
MamillariadeclivisDietr。Allg。Gart。Zeit。xviii。235
（1850）。
MamillariaapplanataEngelm。Pl。Lindh198（1850）。
MamillariatexensisLabouret，Monogr。Cact。89（1858）。
Depressed，globose，usuallywithdepressedvertex，8to12cm。
broad，2。5to5cm。high：tubercleselongated：radialspines10
to22，whitish，5to12mm。long，thelowerusuallythelonger，stouter，andoftendarker；centralspine4to8mm。long，lightyellowish-brown，stout，straight，andporrect：flowers2to2。5
cm。long，reddish-white：fruitincurved，1。5to3cm。long。（Ill。
Cact。Mex。Bound。t。9。figs。4-14）。Typeunknown。
FromtheGuadalupeRiver，Texas，tothemouthoftheRioGrande，andwestwardtoArizonaandSonora。Fl。April，May。
Specimensexamined：Texas（Lindheimerof1845，1847，1853；Wright226，alsocollectionsof1849，1852，1853，1855，1856；Bigelowof1853；Treleaseof1892；Nealleyof1892）：NewMexico（Wright311；
Bigelowof1853，Evansof1891）：Arizona（Pringleof1881）：alsogrowinginMo。Bot。Gard。1893；andintheWorld’sFaircollectionofMrs。Nickels。
Theradialspinesaresomewhatvariableinrelativelength，oftenbecomingalmostequal，whilesometimestheupperradialsareverymuchreduced。ThefigurereferredtoinCact。Mex。Bound。isnotsatisfactoryastothegeneralhabitoftheplant，whichisflat-toppedratherthanhemispherical。
6。Cactusheyderihemisphaericus（Engelm。）。
MamillariahemisphaericaEngelm。Pl。Lindh。198（1850）。
Differsinbeinghemisphericalinsteadofflat-topped，initsfewer（9to12）andshorter（4to8mm。）radialspines，andmuchsmallerlessroughandlighter-coloredseeds。（Ill。Cact。Mex。
Bound。t。9。figs。15-17）Type，the"Goebel’sGarden"plantsinHerb。Mo。Bot。Gard。
ThroughoutsouthernTexasandsouthernNewMexico，andsouthward；
notextendingsofarnorthorwestasthespecies，andapparentlynotsoabundantwithintheUnitedStates。Fl。May。
Specimensexamined：Texas（Schott322，614）：NewMexico（Evansof1891）：alsospecimenscultivatedintheGoebelGarden，St。Louis，in1847，broughtfrom"belowMatamorasontheRioGrande"bytheSt。LouisVolunteers，in1816。
Onaccountofitsconvextopthevarietybecomessomewhathigherthanthespecies（5to7。5cm。），andtheflowersaresometimesslightlylonger（2to3cm。）。
7。Cactusmeiacanthus（Engelm。）Kuntze，Rev。Gen。Pl。260
（1891）。
MamillariameiacanthaEngelm。Syn。Cact。263（1856）
Hemisphericalorwithdepressedvertex，7。5to12。5cm。indiameter，withabroadtop-shapedbase：tuberclescompressed，14
to18mm。long：radialspines5to9（usuallyabout6），stoutandstronglysubulate，6to10mm。long，straightorsomewhatcurved，whitishoryellowish，thelowermostlyalittlelonger，theupperonesometimeswanting；centralspineshorterandstout，darker，straight，andporrect，turnedupwardsamongtheradials，orrarelywanting：flowers2。5to3cm。long，reddish-white：
fruitincurved，2to3cm。long。（Ill。Cact。Mex。Bound。t。
9，figs。1-3）。Typespecimensarethoseofthecollectionsof1847，1851，1852，and1853，fromwhichtheoriginaldescriptionwasdrawnandallofwhichareinHerb。Mo。Bot。Gard。
FromtheGuadalupeRiver，Texas，tothe"GreatBend"oftheRioGrande，westwardthroughwesternTexasandNewMexico；alsonorthernMexico（Hemsley）；Fl。May，June。
Specimensexamined：Texas（Wrightof1851，1852；Bigelowof1853）：NewMexico（"MissouriVolunteers"of1847；unknowncollectorin1880）；alsospecimenscultivatedinSt。Louisin1853，andothersgrowinginMo。Bot。Gard。1893。
Dr。EngelmannregardedthisspeciesaspossiblyonlyavarietyofC。heyderi，towhichitiscertainlyverycloselyalliedthroughvar。hemisphaerica，butthedifferenttuberclesandfewerstouterspinesservesowelltodistinguishitthatitseemsbesttoretainitsspecificrank。
Inreferencetothecitationoftheoriginaldescriptionanexplanationseemsnecessary，whichwillapplytonumeroussimilarcases。ThePacif。R。Rep。iv。27（1856），Syn。Cact。263
（1858），andCact。Mex。Bound。9（1859），haveeachbeencitedastheoriginalpublication。Theconfusionhasarisenfromthefactthatinboththepublicationsof1856thedescriptionintheRep。Mex。Bound。isreferredto，andinthatreporttheplantisfullydescribedas"sp。nov。"However，thepublicationoftheBoundaryReportwaslongdelayedonaccountofthepreparationoftheplates，andinthemeantimeboththepublicationsof1856hadappeared，ineachoneofwhichthespeciesisdistinctlycharacterizedandreferencemadetothedescriptionintheforthcomingBoundaryReport。Asbetweenthetwopublicationsof1856theSyn。Cact。（Proc。Amer。Acad。
iii。259）wasevidentlydistributedfirst。
8。Cactusgummiferus（Engelm。）Kuntze。Rev。Gen。Pl。260
（1891）。
MamillariagummiferaEngelm。Wisliz。Rep。21（1848）。
Hemispherical，7。5to12。5cm。broadand6to10cm。high：
tubercles12to15mm。long：radialspines10to12，thelowerstout，withduskyapex，12to15mm。long，twiceorthriceaslongasthewhitishsetaceousupperones；centralspine（sometimestwo）shorter（about4mm。），stout，duskyandporrect：
flowers3cm。long，reddish-white，brownish-redoutside：fruitunknown。（Ill。Cact。Mex。Bound。t。9。figs。18-20）Typeprobablylost，asnospecimenscouldbefoundintheEngelmannHerbarium。
Chihuahua，nearCosihuiriachi。
Sofarascanbediscovered，thisspecieshasnotbeencollectedsincetheoriginalWislizenuscollectionof1846-47。TheplantswerecultivatedbyDr。Engelmannandmadetobloom，showingtheflowerstobelargeranddarkercoloredthanintherestofthegroup，fromwhichthespeciesalsodiffersinitsmorerobusthabit，itsveryunequalradialspines，andtheoccasionaloccurrenceoftwocentrals。
**Centralspinehooked。
9。Cactusuncinatus（Zucc）Kuntze，Rev。Gen。Pl。261（1591）。
MamillariauncinataZucc。inPfeiff。Enum。34（1837）。
MamillariabihamataPfeiff。inOttoandDeitr。Gart。vi。274（1840）
MamillariaaduncaScheidw。（1845-1849？）。
MamillariadepressaScheidw。（1845-1849？）。
Usuallyglobose（occasionallydepressedorevensubcolumnar），5
to6cm。indiameter（doubtlessbecominglarger）：tubercles8
to10mm。long，woollyintheupperaxils：radialspines4to6，rigid，4to6mm。long，theupperonestouterthantherestandsometimesshorter，reddish-brownandhorny，straightorslightlycurved，theremainderstraightandwhitewithduskytips；centralspinestoutandhorny，reddish-brown，7to10mm。
long：flowersgreenish-whiteortingedwithred：fruitunknownTypeunknown。
EntirelyMexican，reportedfromChihuahuatoSaintLuisPotosi。
Specimensexamined：SanLuisPotosi（Greggof1848；Parry268；
Eschanzierof1891）：Chihuahua（Wislizenusof1846-47；alsoChihuahuaspecimenscultivatedintheJacobyGardenin1856and1857）。
Thevariationsobservedinthisspeciesdonotseemsufficientfortheestablishmentofvarieties。Thetypeformseemstohavebeenglobose，with4radialspinesandastoutcentralone。Thedepressedformswith6radialsandamoreslendercentralrepresentvar。spinosiorLem。（M。depressaScheidw。）；andthesubcolumnarformswith6radials（theupperoneofwhichissomewhatcurved）andastoutstronglyhookedcentralrepresentvarbiuncinataLem。（M。bihamataPfeiff。）Suchcombinationsofcharacters，however，donothold，asanyoneoftheplantbodyformsmaydisplayanyoneofthespinecharactersreferredto。
B。Tuberclesterete。
*Centralspinesnone：mostlysimplegloboseplants，withverynumerousstraightwhitishsetaceousradials。
10。Cactuslasiacanthus（Engelm。）Kuntze，Rev。Gen。Pl。259
（1891）。
MamillarialasiacanthaEngelm。Syn。Cact。261（1856）。
Globoseorovateglobose，2to2。5cm。highand1to2cm。broad：
tubercles4mm。long，about2mm。indiameter，withnakedaxils：
spines40to60，inmanyseries，veryunequal，2to4mm，long，whiteandpilose，theupperexteriorusuallylongerthantherest，theinnermostusuallymuchshorter：flowers12mm。long，whitishorpinkish（petalswithredmedianband）：fruit1to2
cm。long：seedsabout1mm。long，blackishandconspicuouslypitted。（Ill。Cact。Mex。Bound。t。3）。Type，thespecimensofWrightinHerb。Mo。Bot。Gard。
FromwesternTexas（"westoftimePecos，onlowlimestonehills，amongherbage"）toArizonaandChihuahua。Fl。April，May。
Specimensexamined：Texas（Wright121，alsoof1852；Parryof1852）：Arizona（Millerof1881）：Chihuahua（Pringle213，250，258）：alsospecimenscultivatedinSt。Louisin1852and1855。
11。Cactuslasiacanthusdenudatus（Engelm。）。
MamillarialasiacanthadenudataEngelm。Cact。Mex。Bound。5
（1859）。
Larger，2。5to3。5cm。indiameter，withlongertubercles（5to6
mm。），andmorenumerous（50to80）longer（3to5mum。）spineswhicharenakedornearlyso。（Ill。Cact。Mex。Bound。t。4）
Type，WrightspecimeninHerb。Mo。Bot。Gard。
FromwesternTexas（withthespecies）toCoahuila。
Specimensexamined：Texas（Wrightof1852）：Coahuila（Palmerof1880）。
IntheSyn。Cact。Dr。Engelmannmergesthisvarietywiththespecies，andhasbeenfollowedinthisbysubsequentwriters，butthecharactersseemso（distinctivethatitsvarietalrankhasbeenrestored。
12。Cactusmicromeris（Engelm。）Kuntze，Rev。Gen。Pl。260（1891）。
MamillariamicromerisEngelm。Syn。Cact。260（1856）。
Withdepressedtopandveryrarelybranching，1to3。5cm。indiameter：tuberclesverysmall（about1mm。long）andwart-like，crowded，sheddingthespineswithageandgivingthebaseoftheplantatuberculatedappearance：spinesfromwhitetoashy-gray，1to3mm。long；inyoungplantsandonlowertuberclesofadultplantsabout20，equalandradiant；onflower-bearingtubercles30to40，stellate-porrectineverydirection，the6to8upperonestwotofourtimeslongerthantherest（4to8mm。），clavatetowardtheapexandacute（theclavatetopatlengthdeciduous），intermixedwithloosewoolofaboutthesamelengthandformingasmalltuftonthetopoftheplantwhichincludesandpartlyhidesflowersandfruit：flowerswhitishtolightpink，almostcentral，verysmall（6mm。indiameter），muchreduced（3to5
sepals，5petals，10to15stamens，3stigmas）：fruit8to12mm。
long：seeds1。5mm。long，blackandshining。（Ill。Cact。Mex。
Bound。t。1and2。figs。1-4）Type，thespecimensofWrightinHerb。Mo。Bot。Gard。
Onnakedmountaintopsandsides，extremesouthwesternTexas（ValVerdeCountytoElPaso）andsouthwardintoCoahuilaandChihuahua。
Specimensexamined：Texas（Wright227of1849，alsoof1852；
Nealleyof1892）：Coahuila（Bigelowof1853）：Chihuahua（Pringle212）：alsogrowinginMo。Bot。Gard。1893。
Theplantsdenselycoveredabovewithdelicateashy-grayspinesandwithnakedtuberculatebasearereadilyrecognized。Itstillremainsanopenquestionwhethertheflowersaredevelopedfromtheaxilsoftuberclesofthesameseasonorthelastonesoftheprecedingseason。Dr。Engelmanninclinedtothelatterview，asalltheothercharactersoftheplantassociateitwiththe"lateral-flowered"species；andintheabsenceofdefiniteobservationwehaveretaineditthere。IfthenearlycentralflowersindicatethattheyareproducedfromgrowthofthesameseasonthespecieswouldseemtobealliedtoCoryphantha，inwhichgroupitssmallflowersandsmalltubercleswouldbeanomalous。
13。Cactusmicromerisgreggii（Engelm。）。
MamillariamicromerisgreggiiEngelm。Syn。Cact。261（1856）。
Larger（2。5to5cm。indiameter）andbecomingoblong，withlargerglobose-ovatetubercles（2to2。5mm。long），fewerrigidspinesallradiant（interior5to7shorterandstouter，1to2
mm。long；theouter15to18，3to4mm。long），andfruit1。5to2mm。long。（Ill。Cact。Mex。Bound。t。2。figs。5-8）Type，Gregg508inHerb。Mo。Bot。Gard。
MountainridgesnearSaltillo，Coahuila。SaidbyBuddtooccurwithinthesouthernbordersofPecosCounty，Tex。
Specimensexamined：Coahuila（Gregg508；Palmerof1880）。
Itisaquestionwhetherthisvarietydoesnotmerelyrepresentanolderandbetterdevelopedplantthanthoseuponwhichthespeciesisbased。Mr。HarryI。Budd，whohasmadeextensivecollectionsofTexanandMexicanCactiforthemarket，reportsthatitisimpossibletoseparatesharplythevarietyfromthespeciesinthefield，andregardsthedifferencemerelyasoneofage。Unfortunately，onlylivingmaterialofthespeciescouldbeexamined，butitscharactersseemwellsustainedeveninthemostvigorousplants，someofwhichreachthesizeofthevariety。
Throughthisvarietythespeciesisbroughtverynearthefollowing：
14。Cactusbispinus。
MamillariamicrotheleMuhlenpf。Allg。Gart。Zeit。p。11
（1848），notLem。（1838）。
Differsfromthelastform（var。greggii）chieflyinitscespitosehabit，muchlargertubercles，andtwounusuallystoutandshortcentralspines（fideEngelmann，whoexaminedspecimensinColl。Salm-Dyck）。
CreditedtoMexicoingeneral，butsaidbyBuddtooccurwithinthesouthernborderofPecosCounty，Tex。
**Centralspinespresentandoneormorehooked。
Mostlygloboseandsimpleplants（occasionallysomewhatcylindrical）。
15。Cactuswrightii（Engelm。）Kuntze。Rev。Gen。Pl。261（1891）。
MamillariawrightiiEngelm。Syn。Cact。262（1856）。
Globoseordepressedglobose（top-shapedbelow），3to7。5cm。indiameter，simple：tubercles10to12mm。long，withnakedaxils：
radialspines8to12，white（theupperdusky-tipped），pubescent，8to12mm。longcentralspinesmostly2（usuallysidebysideanddivergent），rarely1or3，scarcelylonger，hookedandreddish-black：flowers2。5cm。long，brightpurple：fruitabout2。5cm。long，somewhatsubglobose，purple：seeds1。4mmlong，blackandpitted。（Ill。Cact。Mex。Bound。t。8。figs。1-8）Type，Wrightof1851inHerb。Mo。Bot。Gard。
Highplainsandrockyplaces，fromtheUpperPecos，eastofSantaFe，N。Mex。，southwardthroughextremesouthwesternTexas（betweenthePecosandElPaso），andintoChihuahua（nearLakeSantaMaria）。
Specimensexamined：NewMexico（Wrightof1851；Rusbyof1880）：
alsogrowinginMo。Bot。Gard。1893。
Dr。EngelmanncallsattentiontothefactthatthisspeciesiscloselyalliedtotheMexicanC。zephranthoides（Scheidw。），butintheabsenceofmaterialrepresentingthelatterspeciesnocomparisoncanbemade。IndescriptionsoftheMexicanspeciesthedifferentlycoloredflowersandthemuchlongerspinessuggestdifferencesthatanexaminationoffruitandseedcharactersmaystillfurtheremphasize。
16。Cactusgoodrichii（Scheer）Kuntze。Rev。Gen。Pl。260（1891）。
MamillariagoodrichiiScheerinSalmCact。Hort。Dyck。91
（1850）。
Globoseorovate，5to7。5cm。high，subsimple：tuberclesovate，short（3to5mm。），somewhatcorkyandpersistent，withdensewoolintheyoungaxilscontaining5to8stiffbristles：radialspines11to15（theuppermostonesometimeswanting），whiteandrigid，5to7mm。long，entangledwithadjoiningclusters；
centralspines3or4（oftensolitaryinyoungplants），brownish-black，theupperonesdivergentandstraight（rarelyshowingatendencytohook），thelowerlonger（9to10mm。），stouterandhooked（usuallyupwards）：flowers12to18mm，long，thepetalsyellowish-whitewithredmidribs：fruitclavateandscarlet。（Ill。Cact。Mex。Bound。t。8。figs。9-14）Type：ScheersaysthattheplantwasbroughtfromtheIslandof"Corros"
（Cedros？）byDr。Goodrich，and"unfortunatelyperishedinthegardens，"whichgenerallymeansthatthereisnotafragmentofthetypeinexistence。
Indryravines，fromSanDiegoCounty，California，southwardthroughoutLowerCaliforniaandtheneighboringislands（includingGuadalupeIsland）。"Llavina。"
Specimensexamined：California（Parryof1850，1875；Agassizof1872；Parish450of1882atVallecito）：LowerCalifornia（Gabb18
of1867；Brandegeeof1889onMagdalenaIsland，and240of1890
fromSanJosedelCabo）：alsospecimenscultivatedinGard。
Salm-Dyck。
ByamisprintinCact。Mex。Bound，thespecificnameappearedas"Goodridgii，"andthiserrorappearsinalmosteverysubsequentmentionofthespecies，eveninWatson’sBibliographicalIndex，althoughinSyn。Cact。andotherreferencesbyDr。Engelmannthecorrectformappears。
17。Cactuspondii（Greene）。
MamillariapondiiGreene，Pittonia，i，268（1889）。
Ovalorcylindrical，fromlowto30cm。high，simpleorsparinglybranched：radialspines20to30，whiteandslender；centrals4
or5，thelongestover25mm，long，rigidandstronglyhooked，darkbrownabovethemiddle：flowersnearly5cm。long，bright，scarlet：fruitunknown。Type，PondspecimensinHerb。Greene。
CedrosIsland，offthewestcoastofLowerCalifornia。Fl。
February。
Unfortunately，thetypespecimenhasbeenmislaid，sothatnoexaminationofitcouldbemade。EvidentlyrelatedtoC。
goodrichii，butdifferinginitsmuchmorerobusthabit，morenumerousradials，muchlongerspines，andlargerscarletflowers。
18。Cactusbarbatus（Engelm。）Kuntze，Rev。Gen。Pl。261（1891）。
MamillariabarbataEngelm。Wisliz。Rep。22（1848）。
Depressed-globose，about4cm。indiameter，simple：tubercles8
mm。long，withnakedaxils：radialspinesverynumerous（50to60），intwoseries，6to8mm。long，theouter（about40）slenderbutrigidandwhite，theinner（10to15）alittlestouterandyellow；usuallyonecentralspine，stoutanderect，hookeddownwards，brownish：flowers18to20mm。long，rose-red：fruitoblong，10to12mm。long，green（whenmature？）：seedsminute，darkbrownandlightlypitted。（Ill。Cact。Mex。Boundt。6。figs。
9-12）Type，Wislizenusof1846inHerb。Mo。Bot。Gard。
CentralChihuahua。Fl。May，incultivation。
Specimensexamined：Chihuahua（Wislizenusof1846，1850）：alsospecimenscultivatedinBaumann’sGardenin1857，1858；alsogrowinginMo。Bot。Gard。1893。
Dr。Engelmannobservedacuriousintermediatecharacterintheoriginoftheflowersofthisspecies，thefirstonesoftheseasonappearingintheaxilsofthelasttuberclesoftheprecedingyear，whilethelateronesdevelopfromtheaxilsofthefirsttuberclesofthesameseason。ThespecimengrowinginMo。Bot。Gard，in1893had3centralspines，oneortwobeinghooked。
19。Cactusgrahami（Engelm。）Kuntze，Rev。Gen。Pl。260（1891）。
MamillariagrahamiEngelm。Syn。Cact。262（1856）。
Globoseoratlengthovate，2。5to7。5cm。high，simpleorbranchedfromthebaseandevencespitose：tuberclesovate，6mm。
long，dilatedatbase（corkyandpersistentwhenold），withnakedaxils：radialspines15to30inasingleseries，white，oftendusky-tipped，slenderbutrigid，nakedorpuberulent，6to12mm。
long，theshorteronesuppermost，thelongeroneslateral；
centralspines1to3，blackishfromapalerbase，thelower（oftentheonly）onestouterandlonger（6to18mm。），hookedupward，theoneortwoupperones（whenpresent）shorterandslenderer，divergent：flowers2to2。5cm。long，rose-colored：
fruit2to2。5cm。long：seeds0。8to1mm。long，blackandpitted。（Ill。Cact。Mex。Bound。t。6。figs。1-8）Type，Wrightof1852andBigelowof1852inHerb。Mo。Bot。Gard。
Inrockyplaces，fromthemountainsofextremesouthwesternTexas（westofthePecos）tosouthernUtah，southernCalifornia（commonalongtheColorado），andSonora。Fl。June-August。
Specimensexamined：Texas（Wrightof1852；Newberryof1858；G。
R。Vaseyof1881；Millerof1881；Briggsof1892）：NewMexico（Evansof1891）：Arizona（Bigelowof1852；Schottof1858；Cousof1865；Palmerof1869，1870；Engelmannof1880；Pringleof1884）：Utah（Parryof1874）：Sonora（Schottof1853）：alsospecimenscultivatedintheMo。Bot。Gard。in1881。