LKMAIREOCEREUS. 



lOI 



20. Lemaireocereus humilis sp. nov. 



Stems weak, forming dense thickets, dark green, i to 4 meters long, about 4 cm. thick, usually 

 with few branches or none; ribs 3 or 4, sometimes 6, more or less interrupted, little undulate; areoles 

 borne in the depressions of the ribs, large, white-felted, bearing spines only in the lower part; spines 

 5 to 8, brown becommg white, acicular, i to 2 cm. long; flowers greenish white, about 6 cm. long- 

 outer perianth-segments hnear-oblong, spreading; ovary with small scattered scales, at first without 

 spines; fruit very spiny, spherical, 4 cm. long. 



IG. 150. Flowering branch of l^emaireocereus humilis. 





Fig. 151. — L. humilis: a, cross-section of stem; b, longitudinal 

 section of rib; c, cluster of spines; d, flower; e, fruit. 



h , 



H. Pittier at Venticas del Dagua, Dagua Valley, Western 



Colombia, altitude 700 to 1,000 meters 



him 



York 



and from his field notes and 



detailed and habit photographs. It is called tuna Colorado. 



from the other species in its slender stems 



fruit of this genus. 



tendency to form 



from a photograph taken by Henry 



150 shows a flowering branch, and figure 151 shows details of the type. 



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