BIRDS OF NOETH AND MIDDLE AMEKIOA. 253 



distinctly (usually not at all) notched, and never distinctly angulated 

 (deflexed) basally. Nostril usually roundish and nonoperculate," 

 usually completely hidden by an antrorse latero- frontal tuft.* Rictal 

 bristles distinct. Wing variable as to relative length; long and 

 pointed in subfamily Corvinse, short and rounded (often much shorter 

 than tail) in subfamily Garrulinse; outermost primary (tenth) short, 

 usually about half as long as ninth, or a little more; eighth to fifth 

 primaries longest Tail very variable as to form and relative length, 

 but never emarginate nor forked; usually more or less rounded, often 

 graduated (sometimes excessively so). Tarsus longer than middle toe 

 with claw, variable as to relative thickness; acrotarsium distinctly 

 ecutellate;'^ lateral toes much shorter than middle toe (the inner 

 usually longer than the outer); middle toe with its basal phalanx 

 united for about half its length to both lateral toes; hallux, with claw, 

 shorter than middle toe, with claw, not longer than lateral toes (often 

 shorter). 



The preceding diagnosis is not entirely satisfactory and can only be 

 regarded as a provisional one, since authorities are by no means 

 unanimous as to the limits of the Corvidse. This uncertainty as to the 

 proper limits of the famil}' has necessitated the framing of a diagnosis 

 specially applicable to the American forms. Several of the Old World 

 types which have been referred to the Corvidse are more or less aber- 

 lant, and some of them certainly do not belong here. Among the 

 latter may be specially mentioned the Australian genus Strepera, which, 

 with the genus Oractictis, has by some authors been referred to the 

 Laniidse, though a more consistent view of their relationship would 

 entitle them to the rank of a family, Streperidse.'^ 



Besides the Streperidse and Laniidse, the nearest relations of the 

 Corvidse seem to be the Paradiseidse, which, according to Dr. Sharpe,' 

 differ chiefly in the abnormal character of the feet, which have the 

 outer toe but little shorter than the middle one, and the hallux, includ- 

 ing its claw, equal to or longer than the middle toe, with its claw. 



Some of the smaller Corvidae of the subfamily Grarrulinse present a 

 remarkably close general resemblance to the Paridse, notwithstanding 

 the great difference in size. Nevertheless, the resemblance seems to 

 be a purely superficial one, since the internal structure does not bear 



« Longitudinal and operculate only in genus Cyanocephalus. 



!* Wholly exposed, the tufts being absent, in genera Cyanocephalus, Calocitta, and 

 Psilorhinus among American genera. 



« Booted in the Palsearctic genus Pregilus, which, together with Pyrrhocorax, is 

 otherwise aberrant, the two constituting the subfamily Fregilinee of some authors. 



''See Parker, Trans. Zool. Soc. Lond., ix, 1875, 337, and Newton, Dictionary of 

 Birds, pt. i, 1893, 116. 



According to Parker the true Corvidse are segithognathous, while Gymnorhina 

 is compoundly segithognathous or desmognathous by "ankylosis of the inner-edge of 

 the maxillaries with a highly ossified alinasal wall and nasal septum." 



«Oat. Birds Brit. Mus., iii, 1877, 4. 



