Appeared in:

 Britton & Rose's The Cactaceae

  Vol. 4 pp. 130-131:

"1. Trichocereus thelegonus (Weber).
   Stems procumbent or sometimes with erect branches, elongated, 4 to 10 dm. long, dark green, cylindric, 4 to 7.5 cm. in diameter;
   ribs 12 or 13, broad and obtuse, divided into prominent, more or less distinctly 6-sided tubercles; areoles circular, felted;
   spines at first brown, some turning gray, others black; radial spines 6 to 8, acicular, somewhat spreading, 1 to 2 cm. long;
   central spine solitary, porrect, 2 to 4 cm. long; flowers white, about 20 cm. long, funnelform;
   outer perianth-segments greenish; axils of scales on flower-tube long-woolly;
   fruit about 5 cm. long, hairy, red,splitting on one side;
   seed black.

Type locality: Tucuman, Argentina.

Distribution: Northwestern Argentina."