90 Mr. O. Salvin on the Birds of the 



I think therefore that Meco, so far as its birds are con- 

 cerned, should be considered an integral part of the mainland 

 of Northern Yucatan*. 



This removes 9 genera and as many species from the list, 

 and leaves 75 genera and 99 species to be examined. 



Of the 75 genera, Melanoptila is the only genus found in 

 the islands and the adjoining mainland to the exclusion of 

 the rest of Central America, and Spindalis is the only genus 

 belonging to the West Indies to the exclusion of the conti- 

 nent. Forty-three genera are common to the islands, the 

 continent, and to some one or more of the West Indies. The 

 remaining 30 (or 31, including Melanoptila) are shared by the 

 islands and mainland to the exclusion of the West Indies. 



It will thus be seen that the relationship of the islands 

 to the mainland is very much closer than it is to the West 

 Indies, so far as regards genera, though Spindalis is a re- 

 markable exception. 



Next, as regards species, of which there are 99 to be con- 

 sidered (i. e. 108, less 9 belonging only to Meco). Of 

 these 17 are common to the islands, the mainland, and one 

 or more of the West Indies ; 67 [i. e. 76, less 9 Meco birds) 

 are common to the islands and the mainland to the exclusion 

 of the West Indies ; 4 are common to the islands and West 

 Indies to the exclusion of the mainland ; and 11 are peculiar 

 to the islands alone. 



Of the 67 species found on the islands and mainland to 

 the exclusion of the West Indies, 10 are found nearly ex- 

 clusively on the mainland immediately adjoining the islands ; 

 the remaining 57 are of wider range. The 10 species are 

 the following : — 



1. Melanoptila glabrirostris. 6. Cyanolyca yucatanica. 



2. Vireo magister. 7. Myiarchus yucatanensis. 



3. Pyranga roseigularis. 8. Centurus dubius. 



4. Spizella pinetorum. 9. Centurus rubriventris. 



5. Icterus auratus. 10. Chrysotis xantholora. 



* I have not been able to find any trace of Meco Islaod on the chart ; 

 but there is a place marked as El Meco on the mainland near the coast 

 opposite Mugeres Island. Mr. Gaumer's labels, however, give Meco 



