308 TiNAGEID^. 



Eucometis cassini is a somewhat aberrant member of the genus Eucometis, agreeing 

 with it in general structure, and in having the sexes coloured alike ; the tarsi and feet 

 are rather stouter in proportion than in true Eucometis, and the colour of the plumage 

 departs from the olive and yellow tints of its allies. 



The first indication of the existence of this species was a female specimen shot at the 

 Falls of the Truando by Mr. Wood, but left as an undetermined species of Tachyphonus 

 by Cassin. 



The receipt of specimens from M'Leannan by Mr. Lawrence enabled that ornitho- 

 logist to describe the species fully. A figure of the bird, also taken from one of 

 M'Leannan's specimens, which accompanies Messrs. Sclater and Salvin's paper on the 

 birds of Panama, made the species still better known. 



The line of the Panama railway seems to be the head-quarters of Eucometis cassini ; 

 for though it has been traced northwards to Costa Eica, it seems a rare bird there. 

 Arce only sent one example from Santiago de Veraguas and none from Chiriqui, and it 

 does not appear in any abundance in Costa-Eica collections. 



Its extension beyond the limits of Central America was proved by Salmon, who found 

 it at Nechi in the Colombian State of Antioquia ; but his only remark concerning it is 

 that the " iris is dark," and the food " fruits &c." ^ It is also probably found in 

 Western Ecuador ; but of this, as yet, we have no proof. 



TACHYPHONUS. 



Tachyphonus, Vieillot, Anal. p. 33 (1816) ; Scl. P. Z. S. 1856, p. 113. 



Eleven species are included in the genus Tachyphonus, no less than six of which occur 

 within our region — two of these, T. chrysomelas and T. nitidissimus, being peculiar to 

 Costa Eica and the State of Panama. The most widely-distributed members of the 

 genus, T. melaleucus and T. luctuosus, both range northwards as far as Costa Eica, and 

 the latter advances still further to Nicaragua. The remaining species, T. xanthopygius 

 and T. delattrii, are both found in Costa Eica, and thence pass southwards into 

 Colombia. 



The bill of Tachyphonus is rather elongated, subconical, and the culmen more or less 

 incurved ; the commissure is undulated, and near the apex is a well-defined notch. The 

 wings are rounded, and the primaries short, the fourth and fifth being the longest. 

 The tail is long and usually rounded. The tarsi and toes are short and rather feeble. 



One of the most aberrant members of the genus is T. chrysomelas, its peculiar 

 coloration, delicate bill, and square tail rendering it very distinct from the more robust 

 species, such as T. melaleucus. 



As regards coloration, black largely predominates in the males-T. melaleucus, 

 1_ luctuosus, T. delattrii, and T. nitidissimus being chiefly of that colour. The male of 

 T. xanthopygius has yellow shoulders and a yellow rump, and is further distinguished 



