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tarsi and shorter wings and tail, which render the group more fit 

 for terrestrial and less adapted to arboreal life. Commencing our 

 subfamily of Thrushes with the six Cathari, we enter Turdus by the 

 typical small Thrushes of N. America, already alluded to, of which 

 there seem to be eight species, difficult to be distinguished inter se. 

 The second group of the genus — a section denominated by Prince 

 Bonaparte Planesticus — in which the sexes are similar, and the 

 throat is either spotted or striated, — is composed of twenty species, 

 amongst which is the well-known Robin of the Americans, Turdus 

 migratorius. A third group, in which the plumage is dusky and 

 uniform, but the sexes are still alike, may be called Semimerula. 

 It is composed of five species. There remain the Black-birds — of 

 the section Merula — in which the sexes are different. Of these in 

 the New World there appear, according to the present state of our 

 knowledge, to be at least six, which make up the large number of 

 thirty-nine species of American Turdi. 



The genera Cichlerminia and Mar gar ops, which in the greater de- 

 velopment of the first spurious primary (always small among the true 

 Thrushes) show an abnormal tendency, contain three or four species 

 peculiar to the Antilles. They may, perhaps, be arranged most 

 naturally next to Turdus — and serve to lead off towards the Mock- 

 birds, the several genera of which follow next in my arrangement. 

 The typical Mock-birds show in many respects striking differences, 

 when compared with the true Thrushes. Being adapted for a life 

 inside the thick bushes and near the ground, they are distinguished 

 by their low crown, their short and graduated wings — the first (spu- 

 rious) primary being much lengthened and generally half as long as 

 the second, — and their longer and more graduated tail. 



These characters and the strongly-developed scutella on the front 

 of the tarsi, which are wanting in Turdus, have induced recent authors 

 to disconnect them entirely from the Thrushes and arrange them 

 with the Wrens. But there are some forms (such as Galeoscoptes, 

 Cichlerminia, and Melanotis) so clearly intermediate in one or other 

 of these respects, that I am unable to draw the line of demarcation 

 between the two groups, and for the present am inclined to consider 

 the affinities of the Mock- birds as closer with the Thrushes than 

 with the Wrens. In their mode of nesting and in the colour of the 

 eggs (points by no means to be neglected in considering natural rela- 

 tionships), the Mock-birds also exhibit Thrush-like characters. 



The series of Mock-birds may be best commenced with Galeo- 

 scoptes — embracing a well-known North American type — and two 

 Antillean species nearly allied to each other, the strong Thrush-like 

 appearance (and habits) of which have induced me to call them sub- 

 generically Mimocichla. Next comes the singular type Melanoptila, 

 of which the nearest ally is perhaps Galeoscoptes carolinensis. Me- 

 lanotis with its two species is also nearly affine to Galeoscoptes, and 

 perhaps hardly separable generically therefrom. Rhamphocinclus 

 and Cinclocerthia, on the other hand, are so aberrant in form that 

 they have been ranged by some authors in a different group altogether; 

 but there can be no doubt that their right place is here. In the 



