69 



Britton, in whose honor the new species is therefore very ap- 

 propriately named. V. umbrosa differs from our species in 

 having uniformly much more elongate petiolules, in its leaflet 

 blades being much less nitidous (especially beneath), its petioles 

 being not enlarged nor club-shaped at their apex, and especially 

 in its petiolules not emerging from enlarged cushions at their 

 base and in its very shortly or obsoletely toothed calyx. V. 

 Brittoniana is known also from Venezuela, French Guiana, 

 Colombia, and Curacao. 



The New York Botanical Garden 



