Islands of the Coast of Yucatan, <S,t. 245 



Mimiis gilvus gracilis, Riclgw. Proc. U.S. Nat. Mus. viii. 

 p. 562. 



Meco I. ; Holbox I. ; Mugeres I. ; Cozumel T. 



These island specimens do not materially differ from those 

 from the mainland, the species being rather variable. 



'f 9. Troglodytes beani. 



Troglodytes beani, Ridgw. Proc. U.S. Nat. Mus. viii. 

 p. 563. 



Cozumel I. 



Many examples of this distinct species. Some of these | 

 have the jugulura tinged with brown, as described by Mr. 

 Ridgway, but in the majority the underside is nearly uni- I 

 form white, the flanks and crissum alone being brown, and 1 

 the latter barred with black. 



~4~ 10. POLIOPTILA C.ESIOGASTER ? 



Polioptila ccerulea casiogaster^, Ridgw. Man. N. Am. 

 Birds, p. 569 ? 



Cozumel I. ; Ruatan I. 



Mr. Ridgway has recently described a bird from the Ba- 

 hamas under the above name, adding to his localities Cozumel, 

 with doubt. As he has birds from both locaHties before 

 him, and I only the Cozumel one, I cannot speak positively 

 as to their specific identity. The Cozumel bird has a darker 

 greyer breast than the true P. ccerulea, and in most cases the 

 bill is wholly black. The latter character I take to be a 

 seasonal one. In Northern Yucatan the true P. ccerulta 

 occurs. 



Mr. Ridgway (Pr. U.S. Nat. Mus. viii. p. 561) includes 

 P. C(Brulea in his list of Cozumel birds without further 

 remark. We have some specimens from Mr. Gaumer's 

 collection made in January that agree well with typical 

 P. carulea, but I am not sure that they are not winter- 

 plumaged birds of the resident species. 



Concerning Polioptila much has been written of late years, "i 

 but T doubt if the right clue to the reason of the many com- 

 plicated points of variation exhibited I)y many of the species 

 has vet been discovered. 



* Vox h^-brida ! 



