BIRDS OF NORTH AND MIDDLE AMERICA. 125 



[Turdus] nigrescens Gray, Hand-list, i, 1869, 258, no. 3763. — ScLATERand Salvin, 



Norn. Av. Neotr., 1873, 2. 

 Merula nigrescens Seebohm, Cat. Birds Brit. Mus., v, 1881, 242 (Volcan de 



Irazu). — RiDGWAY, Proc. U. S. Nat. Mus., v, 1882, 494 (summit Volcan de 



Irazu, Costa Rica). — Bangs, Proc. New Engl. Zool. Club, iii, 1902, 49 Volcan 



de Chiriqui, 10,000 to 11,000 ft.). 

 [Semimenda] nigrescens Sharpe, Hand-list, iv, 190(?, 130. 



Genus TURDUS Linnasus. 



Tiirdus LiNN.EUs, Syst. Nat., ed. 10, i, 1758, 168. (Type, by elimination, Turdus 



viseivorus Linnaeus.) 

 Copsichus (not Copsychus Wagler, 1827) Kaup, Entw. Eur. Thierw., 1829, 157. 



(Type, Turdus torquatus Linnajus.) 

 Ixocossy plius Kaup, Entw. Eur. Thierw., 1829, 145. Type, Turdus viseivorus 



Linnaeus.) 

 Arceuthornis Kaup, Entw. Eur. Thierw., 1829, 93. (Type, Turdus pilaris Lin- 



nseus.) 

 Cichloides Kaup, Entw. Eur. Thierw., 1829, 153. (Type, Turdus atrogularis 



Temminck.) 

 Thoracocincla Reichenbach, Av. Syst. Nat., 1850, pi. 53. (Type, Turdus tor- 

 quatus Linnaeus.) 

 Iliacus Des Murs, Traite Ool. Orn., 1860, 292. (Type, Turdus illas Pallas= 



T. iliacus Linnaeus.) 



Large to medium-sized Tiirdidse, with only three primaries (eighth, 

 seventh, and sixth) sinuated on outer web, outermost (tenth) pri- 

 mary very minute (httle, if any, more than half as long as primary 

 coverts, not more than one-fourth as long as ninth primary), narrow, 

 and pointed, and middle toe (without claw) at least two-thirds as long 

 as tarsus (usually more).** 



Bill much shorter than head, rather stout, deeper than wide at fron- 

 tal antige ; exposed culmen, shorter (or at least not longer) than outer 

 toe (with claw), straight basally, then gradually but not strongly 

 decurved toward tip; gonys much longer than mandibular rami 

 (nearly etpial to distance from nostril to tip of maxilla), straight or 

 very faintly convex, gradually ascending terminally; maxillary to- 

 mium nearly straight (but appreciably concave at or anterior to iniddle 



a This diagnosis covers a group of Palaearctic Turdidae, including many species 

 besides the type (T. viseivorus), some of which, while exceedingly similar to certain 

 Planestici in other characters, including even coloration, nevertheless differ from all 

 the latter in every one of the characters mentioned with the exception of the minute 

 spurious primary, which, however, is so nearly diagnostic in the strictest sense that 

 only one Planesticus (P. migratorius) among all those examined agrees with Turdus in 

 that respect. 



The detailed description of generic characters is, however, drawn up from T. visei- 

 vorus, T. iliacus, and T. musicus alone. It is almost certain that the group in its larger 

 sense should be subdivided, but as the present work is directly concerned with only a 

 single species ( T. iliacus), which occurs in America merely as a straggler to Greenland, 

 I shall not go further into the subject. 



