12 



of Schvialtzia of Small) was perfectly differentiated. More than 

 this, true Schuialtzia is also represented at Florissant ; the species 

 being Sclunaltzia vexans (Rims vexans, Lesq., /. r., 195) ; and, 

 says Lesquereux, this also scarcely differs from living forms. 

 The fact that these groups were wholly separated so long ago, 

 indicates that Greene is right in regarding them as different 

 genera, and that Dr. Small should not be followed in uniting 

 them under Schvialtzia. The Florissant flora also contains a 

 Cotinus, n2iVCi&\y Cotinus fratcrna [Rhts fj-aterna, Lesq.,/. c, 192), 

 closely allied to the Cotinus Palaeocotinus [Rhus Palaeocotinus 

 Saporta) and C. cotinus, of Europe, the first being fossil, the other 

 living. 



When we consider the transformations undergone by the verte- 

 brates since these venerable plants flourished, we cannot help 

 feeling impressed with the permanence of types existing among 

 not merely the lower plants, but the higher as well. It would 

 seem that in estimating genera, such facts should count for some- 

 thing ; and we should not be guided quite so much by the pres- 

 ence of conspicuous outward marks. 



Boulder, Colorado. 



PROCEEDINGS OF THE CLUB 

 November 29, 1905 



This meeting was held at the New York Botanical Garden, 

 with Vice-president Underwood in the chair. Twenty persons 

 were present. 



Dr. D. S. Martin exhibited specimens of glassy cinders formed 

 by the burning of masses of rice-hulls near Charleston, South 

 Carolina, illustrating in a striking manner the presence of silica 

 in these hulls. 



The announced paper of the afternoon was by Dr. N. L. Brit- 

 ton, under the title of " The North American Cactaceae." The 

 speaker remarked that the Cactaceae of North America were 

 being carefully studied by himself in cooperation with Dr. J. N. 

 Rose, of Washington, in anticipation of preparing a systematic 

 account of this group for the " North American Flora." The 

 Mexican forms have been extensively collected by Dr. Rose and 



