272 PROCEEDINGS OF THE AMERICAN ACADEMY 



lines long, and ^ - 1^ lines broad ; other central spines a little shorter. 

 Seed very large, over 14- lines in the longest diameter. — Principally 

 characterized by the few radial spines and the very broad upper cen- 

 tral one, which with the former forms an almost regular circle. 



4. E. POLYANCISTEUS, E. & B. 1. c. : ovatus, s. ovato-cylindricus ; 

 costis 13 - 17 interruptis ; aculeis radialibus sub-19 complanatis albis, 

 superioribus latioribus longioribus, inferioribus setaceis, centralibus 

 difformibus, summo complanato elongate sursum curvato albo, reliquis 

 5-10 teretiusculis purpureo-fuscis, superioribus 2 rectis, ceteris un- 

 cinatis. 



Eastern slope of the California mountains, at the head of the Mo- 

 jave River. — Plant 4-10 inches high, 3- 4 in diameter; radial spines 

 ^ - 2 inches long ; upper central spine 3-5, the others 1 J- - 3^ 

 inches long, the lowest shorter than the others. The number of the 

 hooked spines varies from 3 to 7, according to age and development. 



5. E.UNCiNATUs, Hopf., var. ? Wrightii, E, in B. C. E,. : glauces- 

 cens, ovatus ; costis 13 interruptis ; tuberculis usque ad basin sulca- 

 tis ; aculeis radialibus 8, inferioribus 3 uncinatis fuscis, reliquis 5 

 rectis, centrali singulo angulato complanato flexuoso hamato elongate 

 erecto stramineo apice fusco ; floribus fusco-purpureis minoribus. 



Near El Paso and on the Rio Grande below : fl. ]\Iarch and April. 

 — Plant 3-6 inches high, 2 - 3| inches in diameter ; the tuft of long, 

 erect, straw-colored spines is very characteristic. Lower hooked 

 radial spines about an inch long ; upper ones a little longer ; central 

 spine 2-4 inches long. Flowers l-l^ inches long. Berry fleshy, 

 scaly. Seeds much compressed. — The Mexican E. uncinatus has 

 7-8 radial spines, similarly arranged, and 4 central spines ; the three 

 upper ones not much longer than the upper radial ones and straight, 

 the lower one elongated and hooked. The flower and seed differ 

 also to some extent. 



6. E. SETisPiNus, E. in PL Lindh. 1845 : globosus, ovatus s. sub- 

 cylindricus ; costis 13 compressis acutatis angulatis ; tuberculis bre- 

 vissime sulcatis ; aculeis radialibus 10-16 setaceis; centrali subsin- 

 gulo robustiore terete fusco uncinate s. flexuoso curvato ; floribus 

 magnis flavis intus coccineis ; bacca pisiformi coccinea ; seminibus 

 tuberculatis. 



Var. a. habiatus : aculeis radialibus sub 12, centrali hamato ro- 

 busto. — E. hamatus, Muhlenpf. E. Muhlenpfordtii, Fen. 



Var. /3. sETACEUs : minor; aculeis pluribus, centralibus 1-3 tcnui- 

 oribus vix hamatis. 



