438 BULLETIN 50, TTNITEB STATES NATIONAL MUSEUM. 



Osteological characters.'^ — Interorbital septum nearly closed and pre- 

 palatines broad as in Paridse {Parus), but skull slightly depressed 

 instead of elevated; no fronto-nasal nor maxillo-premaxillary hinge; 

 narial openings elongate ellipses; nasals peculiar in form, with the 

 external process carried for a considerable distance along the pre- 

 maxillary, and the transpalatines and postpalatines but slightly bent 

 downward; prepalatines overlying and fusing with the premaxillaries; 

 a large free lachrymal, much as in Corvidas; quadrate so compressed 

 vertically that the pterygoid lies immediately under, and almost in 

 contact with, the ascending process; pelvis much narrower anteriorly 

 than in Paridse, the ischium and pubis projecting farther downward 

 and backward, and the obdurator foramen connected with the very 

 large obdurator space; arm and manus relatively (compared with 

 humerus) more elongate than in Paridse (very much as in Corvidse); 

 proximal portion of tibia thin and bent inward (much as in Certhia); 

 tibia proportionally shorter than in Paridse, and first phalanx of first 

 digit remarkably long.* 



I find it somewhat diflicult to draw the line satisfactorily between 

 the Sittidse and the Certhiidse, certain genera {Tichodroma and CU- 

 macteris) being distinctly intermediate so far as external characters 

 are concerned, though apparently more nearly related to Certhia than 

 to Sitta; and though disliking very much to differ from so excellent 

 an authority as Dr. Stejneger,". I can not help believing that the group 

 here named Sittidse is much more closly related to the CerthiidEe than 

 to the Paridse, a view which is in harmony not only with Mr. Lucas's 



<* Based on Silta caroUnensis; from Lucas, Proc. U. S. Nat. Mus., xiii, 342, 343. 



6 "Taking all skeletal characters into consideration, the differences between SiMa 

 and the Paridse are such as would seem to preclude their being grouped together, 

 while the peculiarities of the wing of Sitia, slight as they may appear, when added 

 to the other characters, seem sufficient to warrant the assignment of the genus to a 

 separate family." (Lucas, Proc. U. S. Nat. Mus., xiii, 343.) 



The following additional characters of the Sittidae are given by Gates, in his "Birds 

 of British India," i, 298: 



"The intrinsic muscles of the syrinx fixed to the ends of the bronchial semirings; 

 the edges of both mandibles smooth, or the upper one simply notched; hinder 

 aspect of tarsus smooth, composed of two entire longitudinal laminae; wings with 

 ten primaries; tongue nontubular; nostrils clear of the line of forehead, the lower 

 edge of the nostril nearer to the commissure than the upper edge is to the culmen; 

 plumage of the nestling resembling that of the adult female, but paler; nostrils 

 overhung by some hairs; rictal bristles present; rectrices twelve; hind toe and 

 inner front toe very unequal in length; sexes generally different in color; as 

 autumn moult only." 



« With regard to the "quite doubtful" relationships of the Certhiidse Dr. Stejneger 

 says: "The only thing which we know at present with any degree of certainty is that 

 the old notion of the creepers being nearly allied to the nuthatches [Sittidse] is wrong, 

 and that in some way or another they are related to the ' Cinnyrimorphse ' of modern 

 authors." (Standard Natural History, iv, 539. It should be noted that in the work 

 cited, as well as in more recent writings on the subject. Dr. Stejneger treats of the 

 nuthatches as a subfamily, Sittinee, of the Paridee. } 



