Vol. XII. 

 191 



1 Shufeldt, Osteology of Cereopsis nov(B-hollandicB: 221 



In Cereopsis the glosso-hyal is triangular in form, with the apex 

 at the anterior tip, where it is completed with a mere nib of 

 cartilage. Its mid-longitudinal line measures but 15.5 mm., and 

 its greatest width posteriorly, where the lateral angles are some- 

 what produced, 7.5 mm. 



As in Branta, the first and second basibranchials are fused into 

 one piece — the first being of a trapezoidal form and the latter a 

 mere spike extending it posteriorly. Anteriorly, it presents an 

 upper and lower lip, forming an articulation for the glosso-hyal 

 in front of it. From either side of this bone of the hyoid arches, 

 at a point where the basibranchials have co-ossified together, 

 there springs a thyro-hyal, the facet of articulation looking back- 

 wards and outwards. As usual, a thyro-hyal is composed of two 

 pieces, the anterior one being the cerato-branchial, which is here 

 a nearly straight and slender rodlet of bone, measuring some 

 ^y mm. in length, which is equal to the length of that bone in 

 Branta canadensis, only in the latter Goose it is somewhat stouter, 

 more curved, and has a larger head anteriorly. The posterior 

 piece, called the epi-branchial, is not more than half as long as the 

 cerato-branchial, and is uniformly curved throughout its length 

 so as to accommodate itself, in life, to the form of the back of the 

 cranium. Either of these cpi-branchials is concaved for its entire 

 continuity dorsally, and correspondingly convex ventrally, the 

 distal end being tipped with a bit of cartilage. This is also the 

 case with the uro-hyal or sepond basibranchial. 



Branta canadensis has an epi-branchial likewise curved upward, 

 but the bone is semi-cylindrical in form, and thus differs entirely 

 from what we find in Cereopsis. 



In Chen h. nivalis the glosso-hyal is greatly elongated and very 

 narrow. Judging from the dried and roughcd-out specimen at 

 hand (No. 18,611, Coll. U.S. Nat. Mus.), it would apjiear that, in 

 this species, the large tip of cartilage terminating its distal 

 extremity may ossify, and thus form an accessory glosso-hyal. 

 The rest of the apparatus practically agrees with what we find 

 in Branta. 



Throughout the Anseres the bones of the hyoidean apparatus 

 differ, to some extent, for different species and genera ; but they 

 are upon the same plan, and generally well developed. I have 

 examined them for a large number of birds of this assemblage, 

 including Dendrocygna, Hymcnolccmus, Oidemia, Olor, and many 

 of the Anatince and Fiiligiilince. 



So far as I have compared the hyoidean apparatus of Cereopsis 

 novcB-hollandice, I find nothing in its morphology that points to 

 the near kinship of any of the Geese or Ducks I have mentioned. 

 As to Chloephaga, Tachyeres, Coscoroba, and other important 

 forms, I have no material at hand representing the bones of the 

 hyoid arches in them. 



There is considerable literature extant upon the ossifications 

 of the respiratory and vocal organs of the Anserimt ; but, inasmuch 

 as these were not preserved in the only skeleton I have at hand 



