494 SHUFELDT. [Vol. XVII. 



pattern, with the symphysis short and feeble. The anterior 

 moiety of the bone is bent downwards somewhat abruptly, and 

 the ramal sides, from the angle thus formed to the symphysis, 

 are shallow and weak, while the posterior halves are double the 

 height and double the thickness transversely. The superior 

 ramal margin of either limb is rounded off as it passes over the 

 angular bend at the middle of the bone ; and below this point, 

 on the side of the ramus, we note the ramal vacuity, this being 

 much farther forward than we see it in most birds. In a great 

 many pigeons this fenestra is closed in. The mandibular ends 

 are thickened, with their inturned processes short and blunt, 

 while posteriorly their hinder parts are completely and squarely 

 truncated from above, downwards and forwards. 



The hyoidean arches are seen to be very slenderly con- 

 structed in the Columbidce, and to this Ectopistes forms no 

 exception. Rather longish and acute, the glosso-hyal is seen 

 to be preformed entirely in cartilage, as are indeed the slender 

 and projecting cerato-hyals of the anterior cornua. The two 

 basi-branchials are short, delicate rods of bone, and not fused 

 together, where the anterior ends of the even more slender cerato- 

 branchials articulate. Epi-branchials are much shorter, but 

 have about the same caliber as the cerato-branchials. They are 

 tipped with cartilage behind, as is also the second basi-bran- 

 chial. Mr. T. J. Parker, in his description of the hyoid arches 

 of Columba livia {Zootomy, p. 198), found those parts essen- 

 tially the same as I have described them here for Ectopistes, 

 and this account will probably practically agree for all of our 

 United States pigeons. These arches do not depart much 

 from the galline type of structure. 



Of the Skull in Zenaidura macroura. 



Although agreeing closely with Ectopistes, the skull of this 

 species presents us with some few points of difference. The 

 interorbital septum is usually deficient along the track of the 

 first pair of nerves, often as far as the pars plana. Both sphe- 

 notic and squamosal are much reduced, and differ from each 

 other but little with respect to size. 



