■904 MR. F. E. BEDDARD ON THE [ISToV. 26, 



(4) Defixition of the Family PELOBATiDiE. 



Thei-e are not two opinions concerning the validity of the 

 family Pelobatidfe, or respecting the justice of placing in that 

 family all of the genera dealt with in the present communication. 

 Among the matters that require settlement with regard to this 

 family are : the limitations of the several genera which have been 

 assigned to it, their mutual affinities, and the relationship of the 

 Pelobatidfe to other Anurous Batrachia. I pretend to have 

 brought forward in the present communication facts which bear 

 vipon the two important questions above set forth. The facts 

 dealt with in the foregoing pages also permit of some extension in 

 the definition of the family. At the present moment the only 

 characters known which combine to define the Pelobatidee are the 

 following, viz. : — Teeth confined to upper jaw. Vomerine teeth 

 usually present. Omosternum small and cartilaginous, rarely 

 absent *, or larger and calcified t ; sternum mostly with an ossified 

 style. Coracoids overlap (" arciferous " shoulder-girdle). Trans- 

 verse processes of sacral vertebrae large and expanded. Coccyx 

 occasionally fused with sacrum. Tongue round or oval, feebly 

 nicked behind and free (except in Aster oj)hrys). Pupil vertical. 



These characters are not found collectively in any other family 

 of Anura, though all of them singly or in some slight combination 

 are found in other families. To these characters is sometimes 

 added the condition of the tympanum — stated to be " indistinct." 

 This does not appear to me to be a just character as defining the 

 family. Furthermore, there are a certain number of negative 

 characters, such as — ribs absent, no suckers on fingers and 

 toes, (fee. 



To these may be now added two rather important characters — 

 whose possible occurrence, however, in other families requires 

 further demonstration. These are the reduction or even absence 

 of the principal cornua of the hyoid complex, in formulating 

 which I confirm and extend the opinion of Boulenger and Ride- 

 wood ; and the existence of a peculiarly large oesophageal muscle 

 extending in its origin as far back as the middle of the pelvis. 

 The non-union of the two halves of the cricoid and the double 

 character of the often long hypopharyngeal process is characteristic 

 of, though not universal in, this family, and it has not been 

 recorded elsewhere. 



The investigations described in the present paper and others 

 referred to allow of the inclusion of a number of other characters, 

 perhaps of minor importance, in the definition of the family 

 Pelobatidse. So far as we know at present, the thigh-muscles are 

 peculiar in the absence of a deep-seated semitendinosus and the 

 presence of two muscles closely related upon the inner surface of 

 the thigh, which may correspond to the semitendinosus and the 



* In Scaphiopus solitarius. f In JlegalopJir^s nasuta. 



