494 PROCEEDINGS OF THE ACADEMY OF [Oct., 



P. cayana of Linnaeus and allied forms, several of which were described 

 but not named. 



Swainson, 1827, named the light-colored western Mexican bird 

 mexicana, and 1837 modified Linnaeus' name cayanus into cayennensis, 

 which was the form in which it had been used by Brisson. 



Gambel, 1849, described the large Paraguay bird as Piayamacroura, 

 but erroneously credited his specimen to Surinam, as pointed out by 

 Cabanis {Mus. Hein., IV, p. 87). Dr. J. A. Allen (Bull. Amer. Mus. 

 Nat. Hist., V, p. 137, 1893) correctly states that Gambel regarded P. 

 cayana L. and P. mexicana as identical, but his description of macroura 

 could never apply to cayana as Dr. Allen claims. Gambel states that 

 the crissum is black and the length of tail is 15 inches, while P. cayana 

 has a gray crissum and a tail only 9.50 inches in length (Dr. Allen's 

 measurement) ! 



Bonaparte, 1850, also describes the large Paraguay bird as P. circe 

 from a specimen erroneousl}^ recorded as from Colombia (error in local- 

 ity also pointed out by Cabanis, I.e.) and describes as new another 

 bird, P. mehlerijirom Bogota. This name has caused much trouble to 

 subsequent authors. For a time it was used for the small form occur- 

 ring from southeastern Colombia to Ecuador and Peru. Then Dr. 

 Sclater examined the type in the Paris Museum and stated (P. Z. S., 

 1860, p. 285) that it was identical with the east Mexican and Central 

 American bird, claiming that the type locality must have been wrong. 

 Subsequently Dr. Allen and also Mr. Hartert (Nov. Zool., V, 499) have 

 used the name again for the Ecuador bird, and it so stands in Sharpe's 

 Hand List. 



The examination of the type ought to settle a c^uestion of this kind, 

 and I can see no reason why Dr. Sclater's statement should be ignored. 



Cabanis' review of the genus (Mus. Hein., IV, p. 82, 1862) is a remark- 

 ably accurate piece of work. He describes as new the well-marked 

 forms pallescens, guianensis and columbianus, and clearly diagnoses 

 as distinct mexicanus Swainson, macrourus Gambel, nigricrissa Sclater, 

 cayana Linn, and mehleri Bon. His new species mesurus, however, 

 seems not separable from his columbianus. 



In Dr. J. A. Allen's brief review of the genus (Bull. Amer. Mus. 

 Nat. Hist., V, p. 136, 1893) he falls into several errors, largely through 

 lack of material, having no specimens of the light colored bird of 

 northern Colombia and Venezuela, nor of the very large dark form from 

 Paraguay. 



He ignored Cabanis' exlpanation of the true nature of Gambel's 

 macroura, making it a synonym of cayana in spite of the discrepancies 



