Nomenclature of South- American Birds. 241 



is based on Sylvia cayanensis carulea, Briss. Orn. iii. p. SS^, 

 tab. 28. fig. 1. Further, the " Elotototl, Fernand. Mex. 54," 

 is there given as a synonym of it. The diagnosis, '' M. 

 ceerulea ; capistro, humeris, alis caudaque nigrisj" is evidently 

 taken from Brisson^s description. This in general agrees 

 closely with the male of Dacnis cay ana of authors ; but no 

 mention is made (in the otherwise very full and long descrip- 

 tion) of the black throat, a characteristic feature of the male 

 of that species. This omission has been the cause of 

 Brisson's description being, by some authors, applied to 

 Z). angelica, Filippi, which has a blue throat, but otherwise 

 does not at all answer to Brisson's description. 



The consequence has been that great confusion has 

 arisen, two species having been called Dacnis cay ana, viz. 

 D. angelica, Filippi, and D. cyanomelas (Gm.). 



This alone would induce me to drop the name cay ana 

 altogether. 



It is certainly true that we know no other bird to which 

 Brisson's description is better applicable than the species 

 which I call D. cyanomelas (Gm.) ; and therefore it might be 

 assumed that Brisson intended to describe this species, and 

 forgot to mention the black throat. This, however, is not 

 very probable, as the description is long and full, and the 

 plate also does not show any black on the throat. It may 

 be, however, that his description belongs to a different species, 

 differing from D. cyanomelas (Gm.) in possessing a blue 

 (instead of black) throat, and one which has not been seen 

 by naturalists since the days of Brisson, and perhaps is to be 

 rediscovered in the interesting district of Cayenne, where 

 many species exist which, though described by Brisson or 

 Buffon, are now very scarce in collections. I do not say 

 this is probable ; but it is not quite impossible ; and, for the 

 sake of having a well established nomenclature, it becomes 

 necessary to avoid such denominations of that of cayana. 

 Linn. It is hardly necessary to remark that the "Eloto- 

 totl" of Fernandez (cited by Linnaeus as a synonym of 

 his cayana), being a Mexican bird, has nothing to do with 

 our Dacnis cyanomelas. 



