BIRDS OF NORTH AND MIDDLE AMERICA. 321 



Lesser Antilles, and Galapagos Archipelago. (xVbout twelve species, 

 not including subspecies.) 



The above diagnosis and description of external structural charac- 

 ters are drawn up from the type species and others which are evi- 

 dently congeneric, besides two South American species (^1. fhillus and 

 A. ct/<i)ioj>us),^ which, though aberrant, seem scarcely different enough 

 to warrant generic separation. In addition to these typical or nearly 

 typical species of Agelaius^Dv. Sclater includes" six others. Three of 

 these coincide so closely with the typical Agelali in structural details 

 that, notwithstanding great difference in their style of coloration, I 

 am for the present compelled to refer them to the same genus, though 

 of the opinion that differences may be found which will warrant their 

 generic separation. One of these species {Oriolus icterocephalus Lin- 

 naeus) is the type of Xanthommu.^ Cabanis. This species differs from 

 the typical Aglall in having the culmen less elevated ])asaliy. the 

 mesorhinium less flattened, the wing-tip shorter, the toes and claws 

 more slender, and the plumage of the adult male is uniform deep 

 black, with the whole head, neck, and chest yellow. The other two 

 species are closely allied, and one of them {Agelains riijiraj^lllKs Vieillot) 

 is the type of Erytliropmr Cassin. This has the bill ([uite as in typical 

 Agelalits^ but the feet are nmch more slender, with the claws rela- 

 tively longer, and the coloration black, with crown and throat chestnut. 

 A. forhesl Sclater I have not seen, but l)elieve that it should Ije 

 expunged from this genus, since it is said to have the "feathers of the 

 head and neck lanceolate and with shining shafts," the "mesorhinium 

 much flattened," and the base of the mandible denuded and somewhat 

 tuberculate — characters which, quite apart from others that may exist, 

 are certainly not to be found in any species of true Agelaius. A. 

 imthririiil Sclater is so exceedingh' unlike any species of ^4 <7^Z«///.s that it 

 is difficult to understand why it should ever have been placed in that 

 genus. It seems to me far more nearly related to QuUcalus^ and I ha\e 

 accordingly made it the type of a new genus, PseudagehpuK.'' The 

 remaining species, the Oriolus jlavus of Gmelin, has usually been 

 placed in Xanthosonius by those who accord the latter generic rank; 

 but it is b}^ no means congeneric with the type of XoitJKJsonins^ nor 

 apparently with an^^ other species, and having been overlooked ])y 

 Dr. Cabanis, while Mr. Cassin, in his generous distribution of sub- 

 generic names seems to have forgotten it, I have felt compelled to 

 make a new one {Xanthoj^sar)'^ for this species. 



'The first-named of these is the tj'pe of Cabanis' s genua AgelaMicus {^lus. Hein., i, 

 Septeni])er, 1851, 188.) 



'Cat. Birds Brit. Mus., xi, 1886, 339-348. 

 »Proc. Biol. Soc. Wash., iii, Apr. 15, 1901, 155. 



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