INTRODUCTION. XUl 



longer than the fifth. The tail is generally moderate in length, com- 

 posed of twelve rectrices (as is usual in the Insessores), more squared 

 than in most genera of Tanagers. The feet are slenderly built, the 

 tarsi being rather short, but longer than the middle toe, with three or 

 four scutella faintly marked in front, but no indications of them be- 

 hind ; the inner and outer toes are nearly equal in length, the outer 

 being slightly longer ; the claws are short and much curved. 



Such are the characters of the genus Calliste, and, although its 

 members may easily be divided into a certain number of homo- 

 chroous groups — that is, groups in which the species correspond in 

 the general style of their colouring, — it would be difficult, and, in 

 fact, has never been attempted, to assign structural characters to 

 these, — although some writers have considered them as true genera. 

 But these groups are by far the most simple way of arranging the 

 species, and we can use the names which have been made for them 

 as the titles of the different sections, without looking upon them at 

 all in the light of genera. Such is the method employed in my 

 "Synopsis Avium Tanagrinarum," published in the 'Proceedings of 

 the Zoological Society' for 1856, and I have followed the arrange- 

 ment there given in the present volume. 



We commence then our series of Callistce with the group of 

 " Paradise Tanagers," of which three species are known, the New 

 Grenadian C. ccelicolor being scarcely separable from its representa- 

 tive in Guiana. For this section Prince Bonaparte has used the ap- 

 pellation Tatao ; they may be recognized by their glossy velvet-black 

 back, brilliant yellow or red rumps, and the curious bright scaly 

 green feathers of the sides of the head. Next follow very naturally 

 the true Callistce, five in number, exhibiting much variety in plumage, 

 and the last of them, Calliste schranki, obviously leading on to- 

 wards the spotted group, which composes Prince Bonaparte's sub- 

 genus Ixothraupis. These are again five in number, and are distri- 

 buted, as is often the case, over different geographical areas, in which 

 they seem ^o represent one another. They are succeeded by the 

 golden Chrysothraupides, four of which are very closely allied in 

 colouring, whilst the fifth, Calliste icterocephala, is somewhat more 

 idiochroous. In all these four sections the sexes, when adult, are 

 nearly alike, the females being only less brilliant and decided in their 

 tints, but the young birds are occasionally slightly different. In the 



