OP ARTS AND SCIENCES. 115 



been found in sandy fields, hills of Patzcuaro, Michoacan, October, 

 1892 (n. 4258). They show that the plant is 1^ feet or more in 

 height, and that the roots bear fusiform tubers an inch or two in 

 length. 



Spiranthes aurantiaca, Benth. & Hook. var. acuminata. 

 Bracts narrower, acuminate, somewhat exceeding the flowers, the 

 edges involute. Collected by Dr. Palmer in Jalisco, 1886, no. 581, 

 and by Mr. Pringle on foothills of the Sierra Madre, Chihuahua, 1887 

 (n. 1509), and again on swells of low meadows, Valley of Toluca, 

 September, 1892 (n. 4280). 



DioscoREA MINIMA. Glabrous ( $ only seen) : tuber globose, ^| 

 inch in diameter : stem weak, flexuous, 1-3 inches high, about 

 2-leaved : leaves ovate, cordate, acuminate, about 9-nerved, 1 inch or 

 less in length, on petioles 3-6 lines long : staminate spikes 2-4, slender, 

 pedunculate or subsessile, less than an inch in length, rather densely 

 flowered, not manifestly verticillate except below : bractlets linear, 

 two thii'ds as long as the flowers : divisions of the perianth elliptical, 

 obtuse, 14 lines in length, white with a green midvein ; stamens 3, a 

 third shorter than the perianth. — Lava beds near Patzcuaro, Mi- 

 choacan, July, 1892 (n. 4157). This species is nearly related to 

 D. multinervis, Benth., but differs in the form of the leaves and in 

 the length and color as well as somewhat in the arrangement of the 

 flowers. 



In the labels of Mr. Pringle's distribution of 1893 the following 

 corrections are to be noted : — 



4119, Piqueria Pringlei, Rob. & Sea. 



4133, drop mark of interrogation. 



4229, read crassiiiscula, not crassicula. 



4238, Astragalus Tolucanus, Rob. & Sea. n. sp. 



4246, Senecio procumhens^ HBK. 



4296, add ex char. 



