NEW SPECIES OF CHAENACTIS. 221 



ignorant of the ripe pods and seeds of the plant, could possi- 

 bly make a better disposal of it. But the one character essen- 

 tial to the very existence of Cardamine as a recognized genus 

 is extreme elasticity of the valves of the pod when mature. 

 That which lacks the essential character of a genus, must not 

 be forced into such genus ; and I call this type 



PtANODES ViRGINICUM. 



New Species of Chaenactis. 



Chaenactis leucopsis. Subalpine or alpine low peren- 

 nial, the many stems, buried for half their length in sand or 

 scorial, arising from a more deeply seated root, their aerial 

 part consisting of a tuft of leaves and a scapiform monoceph- 

 alous stem, itself barely 2 inches high and little surpassing 

 the leaves, the whole herbage even to the tips of the involu- 

 cral bracts whitened with a fine close altogether wooly indu- 

 ment : leaves of stout petiole and pinnate blade of about equal 

 length, the pinnae approximate and themselves pinnate-lobed 

 all except the lowest, and the minute lobes short and rounded : 

 heads M inch high, about as broad, the bracts subequal, the 

 outer, lance-linear, the others linear, none quite acute ; rays 

 none : achenes hirsute ; pappus of about 8 subequal paleae, 

 all obtuse, purple in the middle. 



Type specimens in U. S. Herb, from an altitude of 11,500 

 feet in the Needle Mountains in southwestern Colorado, 14 

 July, 1901, Whitman Cross, collector. Completely separate 

 from other alpine species by its purely wooly indument, with- 

 out trace of separate hairs or any glands ; its habit also rather 

 characteristic. 



Chaenactis pumii<a. Alpine or subalpine dwarf peren- 

 nial with its several branches wholly above ground, clustered 

 on the crown of a long deep root, the whole plant above 

 ground only 2 to 3 J^ inches high, but the breadth of the mass 

 of heads sometimes 4 inches ; blades of the leaves ovate, often 



