LEMAIREOCEREUS. 



IOI 



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, becoming white, acicular, i to 2 cm. long; flowers greenish white, about 6 cm. long; 

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

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



FIG. 150. Flowering branch of Uemaireocereus humilis. 



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

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



Collected by H. Pittier at Venticas del Dagua, Dagua Valley, Western Cordillera of 

 Colombia, altitude 700 to 1,000 meters, February 1906, and described from a plant col- 

 lected by him (New York Botanical Garden, No. 34794) and from his field notes and 

 detailed and habit photographs. It is called tuna Colorado. 



This plant is quite different from the other species in its slender sterns with very few 

 ribs and in its tendency to form dense thickets, but it has the characteristic flower and 

 fruit of this genus. 



Figure 149 is from a photograph taken by Henry Pittier at the type locality; figure 

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



