TRICHOCEREUS. 



131 



This species has heretofore been unknown to us, but fine specimens, both living and 

 for the herbarium, were obtained by J. A. Shafer at Tapia, Tueuman, near the type locality, 

 February 9, 191 7 (No. 98). 



Illustration: Schumann, Gesamtb. 

 Kakteen f. 14, as Cereus thelegonus. 



Figure 188 is from a photograph of 

 a flowering branch in the garden of Dr. 

 Spegazzini at La Plata, Argentina; fig- 

 ure 189 is from a photograph of the wild 

 plant taken by Dr. Shafer in 19 17 at 

 Tapia, Argentina. 



2. Trichocereus thelegonoides (Spegazzini). 



Cereus thelegonoides Spegazzini, Anal. Mus. 

 Nac. Buenos Aires III. 4: 480. 1905. 



More or less branched above ; trunk 4 to 

 6 meters high, cylindric, 18 em. in diameter; 

 branches more or less curved, ascending, 5 

 to 8 cm. in diameter, obtuse at apex; ribs 15, 

 low, obtuse, at first strongly tubercled by a 

 strong depression between the areoles, but 

 gradually disappearing in age; areoles small, 

 circular, felted; spines 8 to 10, yellow or 

 brownish, setaceous, short, 4 to 8 mm. long; 

 flowers 20 to 24 cm. long, greenish without; 

 inner perianth-segments oblanceolate, acute, 

 white; scales on the ovary and flower-tube 

 hairy in their axils. 



Type locality: Jujuy, Argentina. 

 Distribution: Northern Argentina. 



Fig. 188. — Trichocereus thelegonus 



Living specimens were brought from Argentina by Dr. Rose in 19 15. 



Trichocereus thelegonus. 



3. Trichocereus spachianus (Lemaire) Riccobono, Boll. R. Ort. Bot. Palermo 8: 237. 1909. 



Cereus spachianus Lemaire, Hort. Univ. 1 : 225. 1840. 



Echinocereus spachianus Riimpler in Forster, Handb. Cact. ed. 2. 827. 1885. 



Cereus santiaguensis Spegazzini, Anal. Mus. Nac. Buenos Aires III. 4: 478. 1905. 

 Stem upright, at first simple, later profusely branching at the base; branches ascending parallel 

 with the main stem, 6 to 9 dm. high by 5 to 6 cm. in diameter, columnar; ribs 10 to 15, obtuse, 



