DEVELOPMENT OF THE SKULL IN THE BATRACHIA. 147 



all thiiigs else in this skull. The roof- bones {f-P-) run short in front ; the pai'asphenoid 

 (pa.s.) has pointed arms under the ear-capsules ; the vomers {v.) are wide apart and 

 have only a smallish crop of teeth ; there ai'e no septo-maxillaries ; the premaxillaries 

 {px.) are wide but feeble, so also the maxillaries [mx.) have a wide facial plate, but it is 

 thin; the quadrato-jugals {q-j.) are not grafted on the quadrate; the squamosals are 

 but little developed over the tegmen (fig. 1, sq.). 



Here, in a few things, the "norma" is not reached; besides the general breadth of 

 the parts — 



1. The auditory occipital masses of bone are confluent above. 



2. The lesser fontanelles are very small and have a still smaller space between them. 



3. There are small superorbital projections. 



4. Tliere are no sejito-maxlllaries. 



5. The supra-stapedial is membranous. 



6. The hyo-branchials are feeble. 



This is a poor list of indictments against this species as coming short of the norma ; 

 the flatness of the general shape, and of the individual parts, are also no great modi- 

 fications in the morphology of this very Ranine skull. 



Second genus. Rhacophorus. 



37. Rhacophorus maximus. — Adult male ; 3^ inches long. North India. 



This large species bears the same relation to the Tree-frogs of India that Pelodryas 

 does to those of Australia, and Phyllomedusa to the Neotropical kinds. 



That which characterises the Oriental Polypedatidse, generally, is here carried to 

 excess, namely, the great dilatation of the endocranium, especially m the nasal region. 

 The length is seven-eighths as great as the breadth ; the quadi'ate condyles (Plate 26, 

 fig. 5, 6, q.c.) are opposite the passage for the vagus nerve (fig. 6, X.). 



The cranial " barge," from the foramen magnum to the great transvere snout, is twice 

 the breadth of an average skull of a species of Rana of the same size as this kind. 

 The fore skull, leaving out the massive premaxillaries, is as long as the mid skull, and 

 is wider : it is extremely wide in the ethmoidal region. The mid skull lessens gently 

 to the temporal region, where it is pinched in ; in front it is tliree times as wide as it is 

 deep (figs. 5, 6, 7). 



The antero-posterior extent of the hind skull is half that of either of the other two 

 regions, yet the breadth of the cranial cavity is not lessened there, but the parotic 

 wings extend far out, as the great breadth would indicate, beyond the horizontal canals 

 (fig. 5, h.s.c); these wings are rather narrow. The occipital condyles (occ.) are rather 

 small for so strong a skull, they are posterior, and are sepai'ated by an arched (emar- 

 ginate) line of their own breadth. 



The occipito-auditory ossifications are all continuous, as in Polypeclates chloronotus, 



u 2 



