198 BllITISH BIRDS. 



never a Raptorial tooth as in the Shrikes. The bastard primary is always 

 present — a character which separates the Thrashes from the Wagtails and 

 the Swallows J and also from all the British Finches. In the British 

 examples of the Turdinm it is sometimes very smallj but never so minute 

 as in the Starlings and in the Waxwings. In all of them^ however, it is 

 much narrower than the second primary, and not half as long, a character 

 which will serve to distinguish the British Thrushes from the Crows. The 

 young iu first plumage differ from the adults in having the upper and 

 underparts more or less spotted; but they moult into adult plumage in 

 their first autumn before they migrate. Adults moult only in the autumn, 

 usually attaining their nuptial dress by casting the ends of the feathers, 

 which deepen in colour at the same time. The Turdinm are nearly cosmo- 

 politan, and probably number more than seven hundred species, of which 

 about one hundred are European. Nearly one third of these inhabit our 

 islands, or visit them more or less regularly. The British Tiirdince belong 

 to ten genera. Many of these are so closely related, that they can only 

 be recognized by courtesy or as a matter of convenience. There are no 

 structural characters on which to form a key to the genera. The chief 

 character which has been relied upon is the pattern of the colours, which 

 will be described in each genus. 



Genus GEOCICHLA. 



The genus Geocichla is supposed to have been established by Kuhl 

 about the year 1825; and Geocichla interpres is considered the type; 

 but the original publication of this genus has not yet been found, and is 

 probably in some obscure Dutch periodical. It contains a number of 

 Thrushes distinguished as Ground-Thrashes, and supposed to be the least 

 changed descendants of the ancestors of the true Thrushes and Ouzels. They 

 are characterized by having the basal portion of the outside web of all the 

 secondaries and of many of the primaries whitCj occasionally tinted with 

 buff", but abruptly defined from the brown of the rest of the quills, and 

 forming a peculiar pattern on the under surface of the wing. The axil- 

 laries are particoloured, the basal half being white, and the terminal half 

 black, slate-grey, or brown. Most of the under wing-coverts are similarly 

 particoloured ; but the relative position of the colours is reversed, the white 

 portion being on the terminal half. These characters serve to distinguish 

 them from all other allied genera. 



The genus Geocichla contains about forty species, principally confined 

 to the Oriental and iEthiopian Regions. Three species of the genus 



