106 THE KATUEAL HISTORY EEVIEW. 



directed processes on the ribs, as in the genus Salamandra; they 

 were, however, much larger, had the fronto-parietal bones com- 

 pletely ossified, and the whole of the cranium roughened externally 

 by a dermo-ossification. On this account the genus has been com- 

 pared with CeratophrySy which belongs to the family of Cystigna- 

 thidcB. This dermo-ossification occurs in various families, especially 

 in the New World. 



In the remaining and recent genera, the structure of the sternum 

 is worthy of note. In old individuals of DiscoglossuSy it is some- 

 times fibro-cartilaginous, as in Cystignathus and Fipa. This part 

 is probably homologous, with the xiphisternum of the Lacertilia, 

 while the part commonly called by that name is the united hsBmapo- 

 physial cartilages of the anterior ribs. In the genera in question,* 

 this part is divided nearly up to the point of attachment to that 

 preceding, each moiety being directed outwards and backwards, and 

 tapering into a lateral linea semilunaris. Between these and the 

 pubis there are in Discoglossus the usual three pairs of lineae semi- 

 lunares, connected on the median line by a remarkably strong linea 

 alba. 



In Discoglossus the prefrontalia are strongly developed, being 

 in contact for most of their length, sometimes touching the fronto- 

 parietalia. In Alytes they are also in contact throughout, but are 

 transverse and do not reach the fronto-parietals ; the fontanelle is 

 larger, and the ribs without processes : the whole animal is weaker. 

 In this genus, as well as the preceding, the pupil is a vertical slit ; 

 elsewhere found only in JlylorJiina. A species, A. troschelii,f has 

 left its remains in the miocene Braunkohle along with FalcBohatrachus. 

 Bomlinator is similar to Alytes in its osseous structure, except that 

 the prefrontalia are in contact anteriorly only, and that the sacrum 

 presents but one condyle for the articulation of the coccyx, as is 

 typical of the Asterophrydidce and Aglossa. Along with Alytes and 

 Dactyletlira it has true ossa nasalia, which bound the external nares 

 exteriorly, thus explaining their anomalous position in Breviceps, 

 where they are inferior. In this genus there is no cavum tympani, 

 and the tubas Eustachii are rudimentary or wanting. This 

 character^ is said to be variable, and to be occasionally, more or 



* Duges has given a figure of it in Bomlinator, pi. 3. fig, 24, 

 I Rana troschellii (Von Meyer, Palseontographica, iii . p , 138) is undoubtedly 

 an Alytes. 

 X Vide Glintliei-, Proc. Zool. Soc 1858, p. where Tschudi's remarks are quoted. 



