THE SKELETON 21 



its investing bones, and some account is given of the development. 

 There are unfortunately several inaccuracies in this work which 

 will be referred to in detail in the subsequent description. Gaupp 

 (1898) gives an excellent summary of the work done up to that date 

 but adds little to it. The same author published a similar work in 

 1905 dealing with the development of the skull. In recent years 

 Stadtmuller (1924) has undertaken a complete and detailed rein- 

 vestigation of the development of the skull of the Salamander, and 

 his work has been accepted as a basis for the following investigation 

 of the adult skull. 



As an introduction to this important part of the skeleton it may 

 be well to quote the words of William Kitchen Parker when describ- 

 ing the skull of Salamandra maculosa in 1882 (p. 172): 



'The skull of the adult of this species shows at once the likeness and the 

 unlikeness of this type to that of an average Batrachian; yet in reality this 

 skull differs as much from that of Rana temporaria or of Bufo vulgaris as it 

 did in its early conditions and in the mode of its metamorphosis. But scattered 

 up and down the great Batrachian "order" there are remarkably generalized 

 types whose skulls, now in this and now in that agree with this of the highest 

 kind of "Caducibranchiate" Urodele. I shall, therefore, carefully set down 

 the characteristics of this skull, and then it can be used as a measure, being 

 "perfectissimum in suo genere", of the lowness or height, in type, of the 

 skulls of other Urodeles, and also as a test of what is normal or aberrant in the 

 skulls of the Batrachia. This species and Rana temporaria, therefore, will be 

 taken as convenient, and yet worthy, representative Salamandrian and Batra- 

 chian types. They are culminating forms, being most perfectly specialized 

 according to their kind.' 



These sentiments may well be extended beyond the skull to the 

 animal as a whole, for, just as the Frog is an excellent basic type of 

 Anuran specialization, so the Salamander, considered as a whole, is one 

 of the best examples of Urodele organization, towards which other 

 types may be regarded as leading, or from which they may be derived. 



The general outline of the skull as seen from above or below is 

 roughly that of an equilateral triangle, of which the base-line is 

 drawn through the quadrates. The occipital region extends only 

 slightly behind this line. The jaws are widely spread laterally, thus 

 giving the broad flattened appearance characteristic of Amphibia in 

 general. The orbital rim is incomplete, since the maxilla and quad- 

 rate are connected by a jugal tendon only; there being no osseous 

 bridge. Thus in general shape the skull of the Salamander bears 

 fairly close resemblance to that of the Frog, but in detailed structure 

 they differ widely. 



