Didymopanax Spruceanum, Retiniphyllum spp., Bombaa 
humile and bushy species of Clusia. Apparently it is a 
rare element of the caatingas, since only one flowering 
plant was located during a year’s stay in the region, 
although at least five other vines in sterile condition were 
seen in the same caatinga at San Felipe where the type 
was found. 
Of the 187 South American species of Aristolochia 
treated by Hoehne in his monograph (loc. cit.), thirty- 
nine are known from the Amazon basin, and a number 
of other species, which as yet have not been collected 
from this area, are suspected to occur there. Aristolochia, 
it is evident, is well represented in this part of the con- 
tinent. It is curious that all of the botanical activity along 
the Rio Negro has turned up only four species—ali of 
them endemic to the basin—in this area which is one of 
the richest in diversification of species of plants. A cen- 
tury ago Spruce collected the type of Aristolochia 
Sprucet Mast. at Sao Gabriel, and in the 1880’s Barbosa 
Rodrigues collected A. sylvatica Barb. Rodr. at Mandos 
and A. chrysochlora Barb. Rodr. at Taruma. These three 
species, like Aristolochia Amesiana, are apparently rare 
elements of the flora, for they are known only through 
the type collections. None is closely allied to Aristolo- 
chia Amesiana nor to each other. 
It is an honor for me to dedicate this new endemic, 
albeit belatedly, to the late Professor Oakes Ames, in 
commemoration of his more than fifty years of service to 
Harvard University and his widespread influence as an 
outstanding orchidologist and economic botanist, a 
quietly inspiring teacher and a far-sighted administrator. 
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