NOTES ON THE OSTEOLOGY OF THE PARID^E, SITTA, AND 

 CHAMiEA. 



BV 



Frederic A. Lucas, 



Assistant Cura/or of the Department of Comparative Anatomy. 

 (With Plate XXVII). 



lu studying- any group of osciuine birds it is iuipossible, or at the 

 best extremciy difficult, to tell where to stop, and the question is quite 

 as often decided by the lack of material as by any other cause. 



Thus the present paper is the outcome of a study of the Mimina', 

 which naturally included the Wrens also, acd from them led by way of 

 Chanum to the Titmice, and but for the cause above mentioned might 

 be indefinitely extended. 



Dealing chiefly with North American species these notes are naturally 

 incomplete; but, as the accumulation, proper preparation, and study of 

 osteological material are necessarily slow, they are put forth with an 

 apology for not being more comparative in their nature. 



I give below a list of the species examined and all references to the 

 Paridcc mean the group as thus represented. 



Paras major Parus inornatus 

 ater gambeli 



carolinensia Pealtriparus plmubeus 

 atricapillus iiiinimus 



niontanus Auripanis liaviceps 



budsouicus ^githalus caudatus 



c'ceruleus Chamtpa fasciata 



bicolor Sitta canadeusis. 



The above are all represented in the collections of the U. S. Museum, 

 but I am indebted to Dr. E. W. Shufeldt for the privilege of examining 

 a large number of specimens in his collection. 



In the genus Parus, as here represented, the brain case is large, the 

 beak short, stout, and conical. 



The interorbital septum is well ossified up to the point of exit of the 

 olfactory nerves, although small perforations may be present in the 

 septum, as in Parus hicolor, hndsonicus, gambeli, and inor)iatus. 



The vacuity in the skull at the point of exit of the olfactory nerves 

 is small; much larger in P. hudsonicKS than in any other species ex- 

 amined. 



The premaxillaries and nasals fuse early in life, and are cut squarely 

 across at their posterior extremities, where they are movably articulated 

 with the frontals, as in parrots, the maxillary being also movably ar- 

 ticulated with the premaxillary. 



Proceedings National Museum, Vol. XIII— No. 830. 



Proc. N. M. 90 22 337 



