1908.] NATURAL SCIENCES OF PHILADELPHIA. 493 



color encroaching farther upon the gray abdomen than in any other 

 form. In northeastern Colombia (Santa Marta to Bogota) and the 

 western portion of Venezuela is a light bird of the ''ferruginous" 

 group (columbiana) , practically identical with the form of western 

 Mexico except for its much larger bill. Farther east, from the Orinoco 

 valley throughout Guiana, is another of the chestnut-backed forms 

 (cayana), similar to that from Central America, while to the southwest 

 is still another (nigricrissa) , ranging over eastern Colombia through 

 Ecuador and Peru. Both of these differ from the Central American 

 bird in dimensions and in the almost total lack of brown on the under 

 surface and the tail which is uniform black, while the Guiana form 

 differs further in having gray under-tail coverts instead of dull black. 

 On the island of Trinidad is a diminutive ferruginous-backed bird 

 (insulana), otherwise similar to the Central American form. In 

 southern Brazil, from Bahia and Matto Grosso, is a larger very pale bird 

 (pallescens) of the ferruginous type. 



In Paraguay, and doubtless in parts of Argentina and southern Brazil, 

 occurs the largest form of all (macroura), with a different coloration 

 from any of the more northern races, the back being walnut brown 

 tinged with chestnut. In Bolivia and southern Peru is a smaller race 

 of this same style of bird (boliviana), difieiing further in its gray instead 

 of black under-tail coverts. 



Three of the races of Piaya cayana seem to have been described by 

 early non-binomial authors. Hernandez's Quapactotl being in all 

 probability the east Mexican bird, while Brisson's Cuculus cayenensis 

 is undoubtedly the form from Cayenne and Azara's Tingazu the very 

 large dark bird of Paraguay. 



Linnseus established Brisson's bird in binomial nomenclature as 

 Coccyzus cayanus and Gmelin gave the name. Coccyzus ridibundus 

 to the Quapactotl of Hernandez, quoting the original more or less 

 indefinite description, as was done also by Ray, Buffon and Latham, 

 the last of whom designated it as the Laughing Bird. Later Stephens 

 inadvertently changed Gmelin's name to rubicundus, but added nothing 

 to the original diagnosis. This — ^viz,: "C. fulvus, gula, jugulo, et 

 pectore cinereis, abdomine, femoribus et tectricibus caudae inferioribus 

 nigris. L. 16 ins. Tail half the length of the body. Hab., Nova Hispana " 

 — seems not clearly identifiable, although it is added to the synonymy 

 of Piaya cayana by Capt. Shelly without' question in Vol. XIX of the 

 British Museum Catalogue of Birds, where all these forms are lumped 

 under the above name. 



Vieillot, in 1817, gave the name macrocercus collectively to the 

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