85 



Between the first and second cervical vertebrae there appears, 

 for the first time, in the Chelonians an intervertebral body, form- 

 ing a separate " odontoid bone," which, in the higher animals, 

 becomes the odontoid process. Oken, finding that it had a sepa- 

 rate point of ossification, called it a distinct vertebra, thus making 

 eight in the human cervix. Other authors consider it as the 

 tody of the atlas ; but that this is not true is shown by a speci- 

 men, in the possession of Prof. J. \Vyman,of the fostal condition 

 of these bones, in which the points of ossification for the lody 

 and arches of the atlas are seen, and also a distinct point for the 

 odontoid process. The explanation of Carus seems more satis- 

 factory from this specimen. The body of the atlas is feebly 

 developed, in which it resembles the cranial vertebrse, where the 

 neural arches are much developed, and always at the expense of 

 the body ; to make up in part for this deficiency of body, late- 

 ral articulating processes are developed. As the second vertebra 

 has a very large body, there results an opening between the 

 first and second, which nature fills up, to protect the chord, by an 

 intervertebral body, the odontoid process^ which thus serves the 

 purpose of the body of the atlas ; so that it may be considered 

 analogous, (as performing a similar office,) but not homologous, 

 to the interneural pieces interposed between the neural arches in 

 many cartilaginous fishes, to the interparietals of the rodents, or 

 the temporal and wormian bones in man. 



Dr. Cabot read some notes on the internal anatomy of a 

 female Mina bird, {Gracula reUgiosa,) which he had dis- 

 sected, as follows : — 



Brain large in proportion, skull rather thin. Os frontis more 

 rounded and projecting than in other birds of allied genera which 

 I have examined. Tongue ■{} ins. long, y\ across at base, 

 slightly bifid at tip ; opening of larynx -^-^ in. behind tongue ; 

 OS hyoides projects 1| ins. beyond the tongue, tips cartilagin- 

 ous, jointed at about its middle, the muscle surrounding it rather 

 thick, like that of a woodpecker. Trachea measures 4 inches to 

 its bifurcation. Upper larynx ^ in. long by | ; nothing remark- 

 able about it except, perhaps, rather an unusually large opening. 

 Lower larynx exceedingly muscular, more so by far than that of 



