THE THRUSHES. 49 



FAMILY TURDID^E. THE THRUSHES. 



CHARACTERS. Bill slender, usually distinctly notched, and with distinct rictal bristles. 

 Tarsi booted; i.e., the anterior covering undivided for the greater part of its length. 

 Voting, distinctly spotted. 



All the North American Turdidse have the wing more than three 

 inches long, and may thus be readily distinguished from members 

 of the most nearly related family, the Sylviidse. 



The American Turdidse include two strongly marked sub-families, 

 which may be distinguished as follows : 



Turdinae. Gonys more than one third as long as the commissure. 

 Myadestinae Gonys less than one third as long as the commissure. 



SUBFAMILY TURBINE. THE TRUE THRUSHES. 



ANALYSIS OF GENERA. 



a. 1 Wing less than five times as long as tarsus. 



b.~ First primary not reaching beyond tips of primary coverts. Tail with- 

 out rufous patch at base. 



c. 1 Tarsus not longer than middle toe with claw Hesperocichla. 



c. 2 Tarsus decidedly longer than middle toe with claw. 



d. 1 Second quill shorter than fourth. Tail without white at base. 



e. 1 Tail less than three times as long as the tarsus Turdus (Hylocichla). 



e. z Tail more than three times as long as the tarsus Merula. 



d.- Second quill not shorter than fourth. Tail white at base Saxicola. 



&. 2 First primary reaching beyond tips of primary coverts. Tail with 



rufous patch at base Cyanecula. 



a." Wing more than five times as long as the tarsus Sialia. 



Of the above genera, only Turdus, Merula, and Sialia are, so far 

 as known, represented in the Illinois fauna. The typical species of 

 Turdus are exclusively Old World, a single one (T. iliacus Linn.) 

 occurring accidentally in Greenland. All the American species belong 

 to a very strongly marked subgenus, or perhaps genus, Hylocichla, 

 which differs from Turdus proper in the much more lengthened tar- 

 sus, and other characters. 



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