1908.] NATURAL SCIENCES OF PHILADELPHIA. 497 



Piaya cayana. 



Common characters. Above some shade of ferruginous, bay or 

 wahiut brown, rectrices and remiges with more or less wine purple gloss, 

 tips of remiges dusky, rectrices tipped with white with a subterminal 

 black bar above; central pair usually rusty beneath, others varying 

 from rusty to black in the various races, the white tips always distinct, 

 the subterminal band present or absent, lower surface of body pale 

 gray, thighs sometimes and crissum always darker, throat and breast 

 vinaceous cinnamon. 



The races vary in the color of the upper parts and of the lower side 

 of the tail, as well as in the color of the crissum; the latter, however, is 

 not always constant. There is also marked difference in size, and in 

 the proportions of the bill. 



The extremes of coloration are seen in fresh specimens of P. colum- 

 hiana, nigricrissa and macroura, which on the upper surface are respec- 

 tively ferruginous, bay and walnut brown of Ridgway's Nomenclature 

 of Colors. 



The relationship of the other forms, so far as the color of the upper 

 parts is concerned, is shown below: 



P. c. Columbiana, ferruginous. 



P. c. mexicana, ferruginous. 



P. c. pallescens, ferruginous, a trifle paler. 



P. c. insulana, ferruginous, a trifle darker. 



P. c. nigricrissa, bay. 



P. c. mehleri, chestnut tinged with bay. 



P. c. cayana, chestnut tinged with bay. 



P. c. caucce, similar to the last but more ferruginous. 



P. c. macroura, walnut brown. 



P. c. boliviana, walnut brown. 

 Piaya cayana cayana Linn. 



Cuculus caijanus Linnaeus, Syst. Nat., I, p. 170, 1766 [Cayenne]. 

 Coccyzus macrocercus Vieillot, Nov. Diet., VIII, p. 275, 1817 [Cayenne]. 

 Coccyzus cayanensis Swainson, Class. Bds., II, p. 323, 1837 [Cayenne]. 

 Pyrrhocorax guianensis Cabanis and Heine, IV, p. 85, 1862 [British Guiana], 



Length of wing, 5.65; tail, 11.10. 



Above chestnut strongly tinged with bay, grayer on the head, wings 

 and tail glossed with wdne purple, flanks smoke gray, crissum mouse 

 gray, under side of rectrices dull black except for the white tips, no 

 trace of subterminal bands. 



Some birds have the crissum paler than others. Mr. Hartert at one 

 time {Nov. ZooL, XIII, p. 43) regarded this as a distinctive charac- 

 ter separating the bird of French Guiana from that ranging from 



