ilalu 



■joints S 



ingly different, flat to < 



lindrical 



AA. Articiitations or joints si 

 ilar, more or less flu 

 tened. 

 B. Species from S. America. 



tii2e of joints large: plants 

 mostly large [O. crassa 

 tnoderateiy small). 



Color of spines white 



Color of spines yellow {soiite 

 times red to tvhite in O. 

 JBngelmaiinii, polyantha . 

 crassa,and Ficits-Indica.] 



Spines none or few 



Spines aliiays present, feu 



Brasiliensia 



Galapageia 

 monacantha 

 aurantiaca 

 crinifera 



micTOdasys 



basilaris 



pubenila 



leucotricha 

 , triacantha 

 . candelabriformis 



. Species from S. America. 

 . Joints cylindrical, mostly 

 elongated .S 



, cylindrica 



, vestita 



, clavarioides 



cc. Joints globose to broadly 



oboi-ate 37. Darwinii 



38. diademata 



Fruit ilry. i 



thoi, 



7j,„//...4.-.. Davisii 



4i;. acanthocarpa 

 47. echinocarpa 

 4.S. Bernardina 

 4;i. serpentina 



EE. Fmit fleshi/, proliferous .'lU. prolifera 



51. iulgida 

 EEE. Fruit fleshy, rarely prolif- 

 erous r>L'. Bigelovii 



,'>:i. imbricata 

 54. arborescens 

 .55. spinosior 

 50. Whipplei 



57. versicolor 



58. tetracantha 



wa niing 50. arbuscula 



0(1. leptocaulis 

 01. ramosissima 



1. Brasiliensis, Haw. A larsp, trc-c-Iiki- plant ri-ach- 

 ini; a lici^'ht ot 15-18 ft., numerously branched, with a 

 thick, rmnnlish crown and an upright trunk, 4-6 in. in 

 (liani., anil hearing numerous spines 1 in. or less in 

 length: joints of two kinds, cylindrical, unarticulate, 

 elongate ones and others which are shorter and much 

 flattened and which arise a.s offshoots from the former; 

 the latter leaf-like, thin, 2-6 in. long, oblong, rarely ob- 

 liiTi,L,'-laii >Iatc;' (.r orbicular, dark screen, margin angu- 





2. Galapag^ia, Hemsl. A 

 -10 ft. high, with a circul; 

 ery spiny trunk, 0-8 in. i 



■■ of the species most frequent in cult, 

 it. tree-like plant 

 iliiii,' crown and a 



iiiL; in fragments 

 from the older stems: joints .llipiicjl i.. (.hlong, thick, 

 10-14 in. long: spines at first 3-4, spreading, flexible, 

 increasing in number and size with age, finally cover- 

 ing the joints with long, brush-like bundles: fls. small, 

 less than 1 in. wide, red: fr. subglobose, red. Galapa- 

 gos Islands. 



3. monao4ntha, Haw. An upright plant branching 

 from the ground and reaching a height of 6 or more 

 feet: joints oblong to elliptical, rather thick, terminal 

 ones much thinner, 5-12 in. long, 3-6 in. wide, bright 

 green: areolae with uniformly short wool and yellowish 

 brown bristles; spines 1-2, seldom more, erect, Vi-'W, 

 in. long, yellow to dark reddish brown: fls. yellow, 3 

 in. wide: fr. ellipsoidal to pyriform, occasionally pro- 

 liferous, red, somewhat spiny. Ar},'cnlii»' l{i|.ulilic. 

 — The horticultural variety variegita is in the iradi-. 



4 aurantiaca, Gill. A numerousl I khhIh .1, lalhcr 

 weak, semi prostrate plant 3-5 tt lii.;h Jciinis liiu-ur- 

 1 in( I ol ite to lanceolate, 2-10 m long,' -1 in. wiilc, ellip- 

 tn il 111 tt insMise section, daik green, turgid: afcohe 

 witli I ttitt "t grayish white wool and bright yellow 

 biistOs sjnnes 4-0, spreading, straight, stiff, brown 

 to Mil « till li.iL,'i st li ss than 1 in. in length: fls. yel- 

 low r Jill iMili ti I irniine red, globose, with short 

 s]>iiii s s, a with w .11% hairs. Aigentine Republic. 



cnniferi I I 



soiUii, Parm.). A rauch- 



[ilant, about 3 ft. high: joints 



long and 3-4 in. wide, dark 



areolcB crowded, small, witli 



lib n %<llow bristles, and a 



11 1 ins; spines 6-8. later 



1 in. in length, the 



loped on the under 



-4 m. wide, golden 



