OALLISTEElS. 166 



A Proposed Nev Qenus, Callisteris. 



An early attempt to resolve into natural genera the confused 

 and impossible " Gilia" of Bentham and of Asa Gray, has been 

 for years interrupted ; but I here offer one of the ideas long 

 entertained, namely the segregation of a natural group, all 

 biennials or perennials, and of peculiar habit, of which Pursch's 

 Cantua aggregata is typical. From the Ipomopsis of Michaux, 

 itself an excellent genus and mouotypic, they differ not only 

 habitally and in foliage, but widely in character of calyx and 

 seeds. They are in technical character, far nearer true Gilia, 

 differing therefrom mainly by peculiar habit, biennial or peren- 

 nial root, more fleshy and pectinate-pinnate foliage, a corolla of 

 characteristic configuration and almost always in a maimer 

 bilabiate, the segments not radiating regularly, but one-sidedly 

 to a greater or less degree. Moreover, no Gilia makes any 

 approach to these plants in the peculiarity of their thyrsoid 

 panicled, or really thyrsoid inflorescence. I recognize following 

 geographic species of the genus Callistbbis : 



0. AGGEEGATA. Cantua aggregata, Pursch, PI. i, 147. Calyx- 

 teeth greatly exceeding the short tube, triangular-subulate, 

 slenderly attenuate, herbaceous except laterally near base, 

 hardly spinescent : corolla with rather short lobes very acute. 



Plains and foothills of the Eocky Mountain region eastward 

 and northward. 



0. COLLINA. Calyx-teeth not half as long as the almost cyl- 

 indric tubes, very obtuse, abruptly aristate-pointed, the point 

 straight, rigidly erect : corolla only pinkish, its oblong-lanceo- 

 late very acute lobes reflexed, and irregularly so. 



Bluffs of Clear Creek on the plains not far from Denver, 

 collected by myself, July, 1870. Type in my own herbarium. 



C. LEUCAKTHA. Two feet high, stout, the copious thyrsus of 

 large white flowers a foot long ; calyx subcylindric, purple, its 

 lobes obtuse but each ending in short herbaceous recurved 

 tip : lobes of the very long corolla rather wide, oblong, hardly 

 acute. 



At elevations of 8,000 and 9,000 feet in the Colorado moun- 



