No. 3. 
DESCRIPTION OF THE CACTACEiE. 
BY GEORGE ENGELMANN, M. D., OF gT. LOUIS, AND JOHN M. BIGELOW, M. D. 
MAMILLARIA, Haw. 
I. Eumamillaria. Englm. in Synops. Cact. 
1. Mam. Wrightii, Englm. in Rep. of Bound. Com.: Flowers and fruit were unknown until 
specimens brought from the Pecos flowered in Washington. From these the following descrip¬ 
tion was drawn: 
“Sepalis exterioribus triangularibus obtusiusculis fimbriatis sub-13, interioribus margine 
petaloideis acutis sub-8, petalis (purpureis) lanceolatis acuminatis aristatis sub-12; bacca 
succosa majuscula purpurascente floris rudimentis coronata ; seminibus obovatis basi acutis scro- 
biculatis nigris. (PI. I.) I am not certain whether the flower is actually lateral and the 
germen immersed, whether, therefore, this species actually belongs to the true Mamillaries, or 
to the subgenus Coryphantha; I am, on the contrary, inclined to consider at least the germen 
immersed. I, nevertheless, think it best to leave this species with the Crinitce, to which it 
seems to he so nearly allied, till more complete observations establish the contrary. The flower 
is about one inoh long, petals and margin of inner sepals bright purple ; berry large and pur¬ 
plish ; seeds about 0.7 lines long.” 
High plains near the Gallinas. Hills and rocky places near Anton Chico, on the Pecos, 
September 25, 1853. Santa Rita ,del Cobre mountains, near Lake Santa Maria, Chihuahua. 
Wright and Bigelow, in boundary collections. 
2. Mam. Grahami, Englm. in Rep. B. C. Sand and gravelly banks of streams. Williams’ 
river to the Colorado Grande, January 26, 1854. 
3. Mam. phellosperma, Englm. in Synops. Cact. (M. tetrancistra Englm. in Sillim. Jour., 
Hov. 1852) : Living specimens of this and the preceding species have been brought to Wash¬ 
ington, and are now growing in the Congressional garden. Few specimens only show more 
than one of the 4 central spines hooked. The manifestly improper name previously adopted 
had therefore to be altered. “I have substituted for it a name derived from the peculiar spongy 
or corky appendage of the seed, which greatly resembles that of the seed of Potentillaparadora 
Nutt.” —(Engelmann.) Sandy banks of streams, Colorado Grande and Mohave, February 4-23, 
1854. The external habit of this plant very much resembles that of M. Graliami, and was 
collected in nearly the same localities. 
4. Mam. meiacantha, Englm. in Rep. B. C. : Distinguished from M. applanata by the fewer 
dtad stouter spines, central spine often wanting. Cedar plains near the Llano Estacado to the 
Pecos, September 23-27, 1853. 
