ECHINOCEREUS. 



39 



Collected near Saltillo, Coahuila, April 1898, by Dr. E. Palmer (No. 100). 



This species is common in Coahuila and Chihuahua, Mexico, having been repeatedly 

 collected by Dr. Palmer and others. It is characterized by its stout, stubby habit and 

 by its very long, usually stiff, often bluish spines. 



Figure 47 is from a photograph of a plant collected by Dr. E- Palmer in Mexico in 

 1908. 



54. Echinocereus dubius (Engelmann) Rumpler in Forster, Handb. Cact. ed. 2. 787. 1885. 



Cereus dubius Engelmann, Proc. Amer. Acad. 3: 282. 1856. 



Somewhat cespitose; stems 12 to 20 cm. long, pale green, of a soft flabby texture, 7 to 9-ribbed; 

 ribs broad; spines white; radial spines 5 to 8, 12 to 30 cm. long; centrals 1 to 4, 3.5 to 7.5 cm. long, 

 angled, often curved; flowers pale purple, 6 cm. long or more, with rather few and narrow perianth- 

 segments; scales on flower-tube bearing 1 to 3 white bristles in their axils; fruit very spiny, 2.5 to 3 

 cm. long; seeds covered with confluent tubercles. 



Fig. 48. Flower of Echinocereus 

 dubius. 



Fig. 49. Flower of Echinocereus 

 enneacanthus. 



Type locality: Sandy bottoms of the Rio Grande at El Paso. 



Distribution: Southeastern Texas, perhaps confined to the El Paso region. 



This is said by Engelmann to be near Echinocereus stramineus and E. enneacanthus. 

 The former, however, grows in the mountains and must be quite distinct. It is given a 

 wide range by Schumann, who doubtless has included specimens of one or more related 

 species. We know it only from co-type herbarium specimens of the Mexican Boundary 

 Survey. 



Illustrations: Cact. Mex. Bound, pi. 50, as Cereus dubius; Ann. Rep. Smiths. Inst. 

 1908: pi. 9, f. 3. 



Figure 48 is copied from a part of the first illustration above cited. 



55. Echinocereus* conglomerates Forster, Gartenflora 39:465. 1890. 



Cereus conglomeratus Berger, Rep. Mo. Bot. Gard. 16: 81. 1905. 



Cespitose, forming large clumps; joints simple, often half covered in the ground, 1 to 2 dm. 

 long; ribs 11 to 13, slightly undulate; areoles 1 to 1.5 cm. apart, small, circular, slightly felted; spines 

 white to brownish; radial spines acicular, 1.5 to 2.5 cm. long, spreading; central spines several, 

 elongated, often 7 cm. long, very flexible; flowers 6 to 7 cm. long, broad and open, purplish; perianth- 

 segments broad, 2 cm. long; spines on ovary and flower long, white, more or less curved; fruit globu- 

 lar, 3 cm. in diameter, somewhat acid, edible; seeds numerous. 



*The generic name for this species was given in Gartenflora as Echinocactus in error. 



