76 ON THE STRUCTURES AND DISTRIBUTION OF THE 



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 or auricular ossicles, and the tubas Eustachii are rudimentary or wanting. 

 This character is said by Tschudi and Bruch not to be exceptionless in adults, and 

 that the tubae and tympanum are always present in the young of both this genus and 

 Pelobates. All European. 



Cephalic integument involved in cranial ossification, which completes 

 the o. o. fronto-parietalia. Two coccygeal cotyli and diapophyses ; 

 ribs with posterior process, . . . . . . . . Latonia. 



Cephalic integument involved in cranial ossification ; an open fronto- 

 parietal fontanelle ; no coccygeal diapophyses, two condyles. Tem- 

 poral fossa roofed over, ......... Zaphrissa. 



Cephalic integument free ; a small fronto-parietal fontanelle, (sometimes 

 aijparently closed by the ethmoid.) Prefrontalia largely in contact. 

 Two coccygeal cotyli ; ribs with posterior process. Pupil round. 

 Cavum tympani present. No parotoid glands, .... Discoglossus. 



Cephalic integument free ; a fronto-parietal fontanelle. Prefrontalia 

 in contact throughout. Two coccygeal cotyli. No rudimental digit. 

 Tympanum and cavum tympani distinct. Pupil erect. Parotoid 

 glands present, .......... Alytes. 



Cephalic integument free from cranium ; a fronto-parietal fontanelle ; 

 prefrontalia in contact anteriorly. One coccygeal cotylus. No inner 

 digit developed. No tympanum or cavum tympani ; Eustachian 

 tubes rudimental or wanting. Parotoid glands none, . . . Bombinator. 



LATONIA. 



Von Meyer, Saugetliiere Vogel u. Reptilien von Oeningen, p. 18. 

 L. seyfriedi von Meyer, 1. c. Tab. 

 Habitat. Oeningen, Baden. 



L. r ugosa Cope, Nat. Hist. Review, 1865, 105. Rana rugosa Lartet (Notice sur la 

 Colline de Sansan, p. 41) ; Gervais Palaeontologie Frangaise, p. 494. Tab. 

 ? Rana gigantea Lartet, 1. c. 

 Habitat. Sansan, Southern France. 



On account of the great brevity of Lartet's descriptions, it is not possible to deduce 

 any characters by which to distinguish this species from the last. In both the tem- 

 poral fossa is overarched, as in Cultripes, but in neither is the sacral diapophysis as 

 much dilated as in this genus and Pelobates. The L. r u g o s a may, however, differ 



