IO 



THE CACTACEAE. 



8. Echinocereus triglochidiatus Engelmann in Wislizenus, Mem. Tour North. Mex. 93. 1848. 



Cereus triglochidiatus Engelmann in Gray, PI. Fendl. 50. 1849. 



Cereus gonacanthus Engelmann and Bigelow, Proc. Amer. Acad. 3: 283. 1856. 



Cereus paucispinus Engelmann, Proc. Amer. Acad. 3: 285. 1856. 



Cereus hexaedrus Engelmann and Bigelow, Proc. Amer. Acad. 3: 285. 1856. 



Echinocereus paucispinus Riimpler in Forster, Handb. Cact. ed. 2. 794. 1885. 



Echinocereus gonacanthus Riimpler in Forster, Handb. Cact. ed. 2. 806. 1885. 



Echinocereus hexaedrus Riimpler in Forster, Handb. Cact. ed. 2. 807. 1885. 



Echinocereus paucispinus triglochidiatus Schumann, Gesamtb. Kakteen 281. 1898. 



Echinocereus paucispinus gonacanthus Schumann, Gesamtb. Kakteen 281. 1898. 



Echinocereus paucispinus hexaedrus Schumann, Gesamtb. Kakteen 281. 1898. 



Always cespitose, with few or many simple stems, these 2 to 6 dm. long, 5 to 8 cm. in diameter, 

 deep green, erect or spreading, 5 to 8-ribbed; spines 3 to 8, various, nearly terete to strongly angled, 

 when young reddish to yellow, but gray in age, usually spreading, often all radial, 3 cm. long or less; 

 flowers scarlet, 5 to 7 cm. long; perianth-segments oblong, obtuse, 3 cm. long; areoles on the flower- 

 tube and ovary few, white-felted, the subtending scales small and red; spines on ovary and flower- 

 tube few, red and white; fruit at first spiny, but in age smooth, bright red, 3 cm. in diameter; seeds 

 1 .6 mm. in diameter or less. 



Figs. 6 and 7. Echinocereus triglochidiatus. 



Type locality: Wolf Creek, New Mexico. 



Distribution: Western Texas, New Mexico, and Colorado. 



The species here described is very variable as to habit and number and kind of spines, 

 and has generally been separated into three or four species; Schumann treated it as a 

 single species with three varieties; we have recognized only a single species, but it is possible 

 that Echinocereus paucispinus which has nearly terete spines should be restored for cer- 

 tain plants in Texas. 



Echinocereus monacanthus Heese (Gartenflora 53: 215. f. 32, with wrong legend) may 

 belong here. It is a small one-jointed plant, 10 cm. long, with 7 ribs, and bears but a 

 single spine at an areole. The flowers and fruit are unknown. The plant is said to be a 

 native of Mexico and Texas. 



Illustrations: Pac. R. Rep. 4: pi. 5, f. 2, 3, as Cereus gonacanthus; Pac. R. Rep. 4: pi. 

 5, f. 1, as C. hexaedrus; Cact. Mex. Bound, pi. 56, as C. paucispinus; Schelle, Handb. 

 Kakteenk. 137. f. 66; Bliihende Kakteen 3: pi. 124; Riimpler, Sukkulenten 139. f. 74; 

 Forster, Handb. Cact. ed. 2. 793. f. 102, as Echinocereus paucispinus; N. M. Agr. Exp. 

 Sta. Bull. 78: pi. 16, as.E. gonacanthus; Pac. R. Rep. 4: pi. 4, f. 6, 7, as Cereus triglochidiatus; 

 Cact. Journ. 2: 18, as Echinocereus paucispinus flavispinus. 



