208 



the; cactaceae. 



these brown-felted and with a cluster of 10 to 15 brown acicular spines, 1 cm. long or less and each 

 subtended by an ovate linear scale; areoles on ovary closely set with clusters of brown acicular 

 spines but no hairs. 



Type locality: La Guayra, Venezuela. 

 Distribution: Venezuela and Colombia. 



Flower description drawn from flower opening in the New York Botanical Garden in 

 June 1917, on specimen obtained from M. Simon in Paris, 1905. 



Fig. 287. — Joint of Selenicereus inermi 1 



X0.5. 



Cereus karstenii was sent by Hermann Karsten from Colombia and was described as 

 near Cereus inermis, but twice as slender. We find, however, that true Cereus inermis, 

 especially in cultivation, becomes elongated and slender. In the Jardin des Plantes, Paris, 

 Dr. Rose found specimens labeled Cereus karstenii which proved to be only slender forms 

 of 5. inermis. In 191 6 Dr. Rose collected 5. inermis at its type locality and obtained fruit 

 of this species for the first time. C. inermis laetevirens Salm-Dyck (Cact. Hort. Dyck. 

 1849. 5 1 - I 85°) is only a name. 



Figure 287 shows a joint of a plant collected by Dr. Rose between Caracas and La 

 Guayra, Venezuela, in 191 6. 



Fig. 288. — Branches of Selenicereus wercklei. X0.66. 



16. Selenicereus wercklei (Weber). 



Cereus wercklei Weber, Bull. Mus. Hist. Nat. Paris 8: 460. 190a. 



Epiphytic, slender, much branched, freely rooting, the young growth producing small swollen 

 knobs at the areoles tipped by small red scale-like leaves ; branches pale green, 5 to 15 cm. in diameter, 



