252 BIRDS OF ILLINOIS. 



SUBGENUS Coturniculus BONAPARTE. 



Cotumiculus BONAP. Geog. and Comp. List. 1838,32. Type, Fringilla passerina WrLS. 

 "GEN. CHAE. Bill very large and stout (except in C. lecontei) ; the under mandible 

 broader, but lower than the upper, which is decidedly convex at the basal portion of its 

 upper outline. Legs moderate, apparently not reaching to the end of the tail. The tarsus 

 appreciably longer than the middle toe ; the lateral toes equal, and with their claws falling 

 decidedly short of the middle claw; the hind toe intermediate between the two. The 

 wings are short and rounded, reaching to the base of the tail; the tertiaries almost as 

 long as the primaries; not much difference in length in the primaries, although the outer 

 three or four are slightly graduated. The tail is short and narrow, shorter than the wing 

 (except in C. lecontei'), graduated laterally, but slightly emarginate; the feathers all 

 lanceolate and acute, but not stiffened, as in Ammodramus. 



"This genus agrees with Passerculus in the short and narrow tail. 

 The wings v are much shorter, and more rounded; the feet shorter, 

 especially the middle toe, which is not as long as the tarsus. The 

 tail-feathers are more lanceolate. The bill is much longer, and 

 more swollen at the base. 



"The essential characters * * consist in the swollen con- 

 vex bill; the short toes, compared with the tarsus; the short and 

 rounded wings ; and the very small, narrow, slightly graduated tail, 

 with its lanceolate, acute feathers (except in the South American 

 C. manimbe). 



"In some respects there is a resemblance to Ammodramus , in 

 which, however, the bill is very much more slender; the wings are 

 shorter, and more rounded ; the tail feathers much stiffer, and even 

 more lanceolate ; the toes extending beyond the tip of the tail ; the 

 middle toe rather longer than the tarsus, instead of considerably 

 shorter." 



"C. lecontei has the same general form, but a much smaller bill." 

 (Hist. N. Am. B.) 



The three North American species differ very strikingly from one 

 another in form, and may be readily distinguished by proportions 

 alone, as follows: 



a. Tail much shorter than the wing, double-rounded. Primaries extending beyond 

 the tips of the largest tertials for about .40 of an inch. 



1. C. passerinus. Bill stout, the culmen slightly depressed in the middle portion. 

 Wing about 2.50; tail, 1.90; culmen, .50; depth of bill, .25; tarsus, .80. 



Z>. Tail about equal to, or even longer than the wing, graduated. Primaries extending 

 very little beyond tips of longest tertials. 



2. C. henslowi. Bill very stout, the culmen not depressed in the middle. Wing 

 about 2.15; tail, 2.10; culmen, .50; depth of bill .30; tarsus, .70. 



3. C. lecontei. Bill very small and slender, the culmen depressed in the middle 

 portion. Wing about 2.10; tail.2.30; culmen,.45; depth of bill, .20; tarsus,.65. 



