BIRDS OF ILLINOIS. 



FAMILY TROGLODYTIDJE. THE WRENS AND MOCKING- 



THRUSHES. 



CHARACTERS. Anterior covering of tarsus distinctly scutellate. Bill slender, some- 

 times lenghtened and more or less arched, the culmen more or lets convex. Wing rounded 

 with the first quill well developed, projecting beyond the tips of the primary-coverts. 



Although the Mocking-Thrushes present several strongly marked 

 characters not shared by the true Wrens, we are compelled for the 

 present to place them in the same family. There can be little 

 doubt, however, that they should constitute a family (Mimidce) by 

 themselves. 



The two so-called subfamilies may be distinguished by the fol- 

 lowing characters : 



Troglodytinae. No rictal bristles. Inner toe united to the middle by at least half of 



its basal phalanx. Wing less than 3. 50 inches. 

 Miminae. Rictal bristles well developed. Inner toe wholly separated at the base from 



the middle toe. Wing more than 3,50 inches. 



Subfamily Troglodytinae. THE WRENS. 



"CHAB. Rictal bristles wanting; the loral feathers with bristly points; the frontal 

 feathers generally not reaching to nostrils. Nostrils variable, exposed or not covered by 

 feathers, and generally overhung by a scale-like membrane. Bill usually without notch 

 (except in some Middle American genera). Wings much rounded, about equal to tail, 

 which is graduated. Primaries ten, the first generally about half the second. Basal joint 

 of middle toe usually united to half the basal joint of inner, and the whole of that of the 

 outer, or more. Lateral toes about equal, or the outer a little the longer. Tarsi scutellate. 



"The impossibility of defining any large group of animals, so as 

 to separate it stringently and abruptly from all others, is well un- 

 derstood among naturalists ; and the Troglodytidce form no exception 

 to the rule. Some bear so close a resemblance to the Mocking- 

 Thrushes as to have been combined with them ; while others again 

 exhibit a close approximation to other subfamilies. The general 

 affinities of the family, however, appear to be to the Turdidce, and 

 one of the best characters for separating the two families appears 

 to exist in the structure of the feet. 



