AMPHIBIANS. 71 



suddenly narrows, so as to become a cylindrical rod ; and the bony tubing having met behind 

 the bar approximates the posterior coracoid in character. This latter bone (cr.) is a stout but 

 rather narrow-waisted ray, having a short suture with the prae-coracoid, and a long one, at right 

 angles with the other, with the scapula ; below, it ends obliquely at the broad epicoracoid 

 band (e. cr.), which is hardened by endostosis. This band narrows considerably as it runs into 

 the prae-coracoid, and the left overlies the right. The Sternum (st.) is most instructive ; for 

 although it is only imperfectly ossified, and has no outer sheath, yet it is very long, rather broad, 

 and the three great divisions into manubrium (prae-sternum), body (mesosternum), and xiphoid 

 process (xiphisternum) are marked out. The first division has its own endosteal patch ; the 

 next sends its patch of bone for some distance into the soft, emarginate, xiphoid region, which 

 has no autogenous bone. 



Example 3. Bufo agua, Daudin and Pr. Max. 



Plate VI, fig. 5, shows the Shoulder-girdle and Sternum of this species of the natural size, 

 and from the lower aspect ; so that the left supra-scapula is not supposed to be cut away as in the 

 last, and, indeed, in most of the figures. 1 



This type comes much nearer to Docidophryne than to Bufo, and the differences between 

 this and the last are of an indifferent nature ; so that I need not give a detailed description. 

 The scapular fenestra is not to be seen in this figure ; the inner face shows it best. The prae- 

 coracoid (p. cr.) is relatively longer, and the coracoid (cr.) straighter than in Docidophryne, and 

 the epicoracoid band (e. cr.) wider in front. The Sternum (st.) is here elegantly formed, the 

 anterior margin being arcuate, and the posterior bilobate with retral angles. There are two 

 patches of internal bone (p. st., and m. st.), and the latter runs into the soft xiphoid (x. st). 



Example 4. Otolophus margaritiferus, Cuv. 



Plate VI, fig. 8, shows the Shoulder-bones of this species a female from the Brazils; as 

 seen from above and magnified three diameters. The supra-scapula (s. sc.) is of great depth, and 

 rather broad ; narrowest at the upper margin ; three-fourths of it is covered with outer bone, and 

 most of the rest is ossified internally. The scapula (sc.), prae-coracoid (p. cr.), coracoid (cr.), 

 and epicoracoid (e. cr.) are quite normal or typical, and are very much like those of Bufo agua , 

 but the Sternum (st.) has only one tract of endosteal bone, which affects nearly all the 

 cartilage. In shape the Sternum is an elegant spatula, and it is relatively of a very large 

 size. 



* 



Example 5. Pelobates fuscus, Wagler. 



Plate VI, fig. 6, shows the parts of the thorax in an adult male of this Austrian Toad, 

 magnified three diameters. This, if there be such a thing, is a generalized form. In general 



1 This is one of the old preparations of Batrachia in the Museum of the College of Surgeons ; it 

 is described as a species Ceratophrys ; but this is corrected in MS. in the visitor's copy of the Cata- 

 logue, see vol. i, p. 121, No. 599. 



