In the figures given by Stipanicic and Reig the ossified parts of the girdle are figured in detail (Fig. 8) and Reig's discussion of it is thorough. The decision to call it firmisternal was taken with some hesitancy, for no median elements are indicated, and the position and shape of those seen is closely similar to the ossified parts in _Ascaphus_ and _Leiopelma_; there is no bony sternum or omosternum. It is safe to suppose that some cartilage lay in the midline between the clavicles and coracoids, but there is no evidence as to its extent, rigidity, or degree of overlapping if any. Apparently, then, there is not sufficient reason to infer that this Jurassic frog had a pectoral girdle comparable with the modern firmisternal type. Piveteau (1955:261) remarks that the only living Anuran that can be compared usefully with _Protobatrachus_ (Triassic) with regard to its pectoral girdle is _Ascaphus_. Again, the extent of cartilage in _Protobatrachus_ (Fig. 8) can only be inferred, and there are no median elements. The agreement with _Ascaphus_ includes the presence, in both, of a separate coracoid ossification situated posterior to the ossified "scapulocoracoid" (actually scapula). This ossification is evidently that shown in _Notobatrachus_ as "coracoid." Direct comparison of the three genera with one another suggests that if we use the term arciferal for any, we should use it for all. In the remote predecessor of Anura, _Amphibamus_ of the Pennsylvanian, the pectoral girdle was less substantial than in many of its contemporaries, but it contained the primitive median interclavicle in addition to the clavicle, cleithrum, and scapulocoracoid. (The figure of Watson, 1940, and that by Gregory, 1950, are of individuals of different ages, the latter being older.) It is clear that the paired elements of such a girdle were held rigid by their attachment to the interclavicle, _via_ the clavicles. Subsequent elimination of the interclavicle in the Anuran line of descent, and decrease of ossification, left a girdle like that of _Protobatrachus_, _Notobatrachus_, _Ascaphus_ and _Leiopelma_. But in several advanced families a more rigid median "sternum," of one or two bony pieces plus cartilage, is developed secondarily, possibly (as Cope, 1889: 247, suggested) in correlation with axillary amplexus.