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Show 1889.] ANATOMY OF BURMEISTER'S CARIAMA. 595 the two Seriemas ; there appears, from what he says, to be no difference between the two species, but his account is a very brief one and confined to the principal characters ; so far as it goes my own observations are quite confirmatory of Gadow's paper. The bird is regarded by Gadow as near to Otis and Grus ; this view is still retained 1 by Dr. Gadow. The osteology and visceral anatomy of Cariama cristata have been worked out by Burmeister 2. In" the course of the following remarks upon the osteology of Chunga, which is compared with that of Cariama, I do not refer in detail to Burmeister's description of the bones; as to the visceral anatomy I have not much to add to Burmeister's description. Cariama is regarded by Burmeister as forming with Psophia a special group closely allied to Cranes and more remotely to Otis and the Rails ; the presumed affinities with Gypogeranus are quite superficial. Burmeister's views of the affinities of the bird are based upon visceral as well as osteological characters, and I propose later on to examine this matter in connection with Psophia, the anatomy of which I am at present studying. I do not enter iu this paper into the affinities of Chunga and Cariama ; I merely attempt to differentiate the two genera and to show that they are to be distinguished by well-marked osteological characters, although in the visceral and muscular anatomy they are very similar. Osteology. The skull of Chunga (fig. 1, p. 596) is decidedly narrower in the orbital region than that of Cariama (ibid. fig. 2). The lachrymal bones project further out from the skull; in Cariama the distal region of each of these bones is bent sharply down and comes to lie at right angles; in Chunga the corresponding bones are only gently curved and therefore appear to have a relation to the skull different from that of Cariama. On the under surface of the skull several well-marked differences between the two types are recognizable. The palatines in Chunga have a nearly straight posterior margin, which lies therefore in a direction nearly at right angles with the lateral margins of the bone. In Cariama the angle formed by the external lateral and the posterior margins of the bones is greater ; that is to say, the posterior margin of the palatine bone does not coincide so nearly with the direction of the transverse axis of the skull as it does in Chunga. The maxillo-palatines of Chunga extend further forwards than in Cariama and each narrows gradually towards its anterior extremity ; in Cariama, on the contrary, these bones show a greater deficiency in ossification anteriorly, and so come to be somewhat abruptly 1 " On the Taxonomie Value of the Intestinal Convolutions in Birds," P. Z. S. 2 " Beitrage zur Naturgeschichte der Seriema," Abh. nat. Ges. Halle, i. (1854) p. 17. |