VOL. XVIII, pp. 171-176 JUNE 29, 1905 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



NEW PLANTS FROM NEVADA. 

 IT. 



BY AVEN NELSON. 



The small genus Cleomella seems to have had little attention 

 in late years. In fact, both collectors and herbarium workers 

 seem to have assumed that nothing more remained to be done. 

 Its species being confined largely to the dry arid interior of our 

 great southwest, which is still to a surprising extent unknown, 

 we may expect many accessions to this small group of species 

 when exploration shall be more complete. My attention was 

 called to the genus by some specimens from Prof. P. B. Kennedy 

 that I found difficult to place. To clear up the difficulty I sought 

 the privilege of examining the sheets found in the herbarium of 

 the Missouri Botanical Garden. I wish here to acknowledge 

 with thanks the courtesy of the Director, Dr. Wm. Trelease, in 

 permitting me to examine this considerable series of specimens. 

 As a result of these studies it seems to me that the following 

 should be characterized. In addition to the species of Cleomella, 

 six other new species and a new genus are here described. 

 Cleomella HHImani sp. nov. 



Erect from a tap-root, bright green and perfectly glabrous throughout ; 

 the main axis moderately stout, often simple but usually with a few slender 

 ascending branches from near the base, 1-3 dm. high; leaveslong-petioled 

 (the petiole 1 to 4 times as long as the leaflets); leaflets from oblong to 

 elliptic, generally rounded at both ends, sometimes subcordate at apex, 

 30 PROC. BIOL. Soc. WASH., VOL. XVIII, 1905. (171) 



