,^A4 CACTACE/E. Muviilluriu. 



("oinmoii on siindy or gravelly soil or among rocks about Sun Diego {Parry, Aifnssiz, IlUcha>ck), 

 un.l on the niiglilM.ring islun.l.s, anil southwanl tlirongh tlui rouinsula, /K. (Jiil'h. From 2 or 3 

 lo (! or 7 indicsliigli, 1 lo lA lliick ; tiiliercK^.s '2^ to :5 lini's long ; radial siiincM '2\ to 5, and cen- 

 tral ones 6 to 7 lines long ; llowurB D to I'ilinea in dianiuler, ilirty yellowish tinged with red. 



2. M. Grahami, Ku'^irliii. yimilur tu tlio lust : siiiuHcr, with HiuuUur loss cldsdy 

 pitted amis, but Imi-cr ami more iiuiikuuus (If) lo 'M)) .si-inua, uiul without uxilhiry 

 bristles. — Cact. Mex. liouiiJ. 7, t. G, lig. 1 - 8. 



Common on the most nigge.l rocks on l>oth sides of the Colorado (.VcA(///, Neirlj.rri/), and cast- 

 ward into New Mexico. Heads 1 to a inches high, 1 to 1^ thick. 



3. M. phellosperma, Kngehn. Ovate to cyliiulrical, usually simple : tubercles 

 lung-oval, with wuul ami bristles in their axils, aiul 30 to GO spines at the apex, in 



2 or 3 series ; the outer thinner ami paler; the inner stouter and often darker; the 



3 or 4 central spines stouter, daik brown, and one or several hooked : ilowers with 

 ciliate sepals and 12 to 13 acuminate petals : stigmas 5 : berry obovate or clavate, 

 crimson, containing rather li;w large globose reticulated and warty brown seeds, with 

 a large spungy appentlage. — Cact. Mex. iiound. G, t. 7. 



From the eastern slope of the mountains near San Feliiie to the Mohave country, and through- 

 out Western Arizona. Heads 2 to [> inches high, 1 ^ to 2 inches thick ; tubercles i to 7 lines long, 

 not as much crowded as in the last two species, hut with a nuich larger number of spines, 4 to 9 

 lines in length ; tiower dirty yellowish red, about an inch wide. The seed is partially imbedded in 

 a curious spongy mass, an aril-like enlargement of the funiculus. 



^ 2. Fluircrs liin/cr, vertical, from the base, of a </roovc on the i/ouii<j ur nasctnt 

 tubercles. — CoiiVl'llANTllA. 



4. M. Arizonica, Engelm. n. sp. Globose or ovate ; tubercles long-cylindrical, 

 ascending, deeply grooveil, bearing numerous straight rigid spines : the 15 to 20 

 exterior spines whitish ; the 3 to G interior ones stouter, deep brown above : llowera 

 large, rose-colored : sepals 30 to 40, linear-subulate, fimbriate : petals 40 to 50, 

 lance-linear, awned : stigmas 8 to 10, white: berry oval, green, with obovate com- 

 pressed pitted light brown seeds. 



On sandy and rocky soil in Northern Arizona, from the Colorado eastward (Cones, Palmer, F. 

 Bischojf), and into Soutliern Utah (./. E. Johnson) ; probably in Southeastern California, l-arger 

 in all its jiarts than the foregoing sjiecies ; 3 or 4 inclies thick ; tubercles au inch long ; spines 6 

 to 15 Uncs long ; (lowers 2 to 2^ inches wide, very showy. 



2. ECHINOCACTUS, Link & Otto. 

 Flowers about as long as wide. Ovary covered with sepaloid scales, naked or 

 woolly in their axils. Fruit succulent or sometimes dry, covereil with the persistent 

 calyx-scales, sometimes enveloped in copious wool, and usually crowned with the 

 persistent remnants of the lloAver. Seed obliquely obovate, black. Embryo curved 

 over the small albumen ; cotyledons parallel to the sides of the seed. — Mostly 

 larger, sometimes gigantic, globose or depressed, or ovate, or rarely subcylindric, 

 simple or very rarely cespitose ; bunches of spines on the more or less vertical ribs. 

 Flowers contiguous to and above the sjiines, on the latest growth of the jdant, often 

 from the nascent woolly areola) and therefore more or less vertical, open only in 

 sunlight. 



* Scales of the ovary ovate, orbicular, or cordate, and mostly fringed, their axils 

 almost naked: fruit scaly, never woolly. — Leiocarpi. 



+- Spines smooth. 

 1. E. Whipple!, Engelm. & Big. Heads solitary, globose or ovate, middle-sized, 

 with 13 (to 15) compressed and interrupted ribs : of tlie 7 to 11 outer and 4 inner 

 spines, the ivory-white upper ones are the longest and l)ruadest and recurved or 



