DEVELOPMENT OF THE SKULL IN THE BATRACHIA. 41 



are nnossified ; the floor is wide in front and narrower behind, whilst the contrary is 

 seen in tlie roof. The subnasal angles are well developed; the pro-rhinals {iJ.rh.) are 

 large, elegantly pedate, and turned outwards and downwards : there is a distinct 

 prenasal rostrum more than half their length. The cake-shaped inner, and the shell- 

 like outer, upper labials {u.V.u.l-.) are well developed. The large palato-suspensorial 

 arch is but little affected by the bones investing it, — the palatal and the pterygoid 

 {pa.,p<j.); but these are normal and well-developed; there is no metapterygoid, and 

 the part above the quadrate liinge is largely ossified by the quadrato-jugal {q., q.j.). 

 The hinge reaches to opposite the stapes ; its stem is strongly clamped on the inside by 

 the pterygoid, and on the outside by a well-developed squamosal [sq.), whose supra- 

 temporal and postorbital regions are rather larger than in R. temporaria. Over its 

 descending part is the "annulus" {a.ty.), which is also larger than in the type, and 

 it is also completed into a ring above. The Eustachian opening (eu.) is large, and the 

 stylo-liyal end of the hyoid bar (st.h.) is confluent with the lower part of the ear- 

 capsule behind this passage. 



The stapes and columella are large and well developed, but the solid inter-stapedial 

 mass of cartilage is not segmented off from the medio-stapedial bar (fig. 10, i.st.,m.st.,st.) ; 

 the extra-stapedial {e.st.) is not spatvdate, but orbicular, and the strong supra-stapedial 

 (s.st.) is confluent with the auditory roof The mandible (fig. 8) has the dentary broad 

 and ascending behuid the mento-Meckelian ; the hyo-brancliial plate (fig. 9, hJiy.) has 

 a broader hypo-hyal lobe than in the Common Frog. 



The fronto-parietals (f.p.) are rounder and thinner, the parasphenoid relatively 

 larger, but the prsemaxillaries, maxillaries, and nasals agree very closely with those of 

 the type ; the quadrato-jugal, however, differs : it is largely grafted on the quadrate 

 cartdage (figs. 6, 7, /.p., n., p)x., mx., px^-s., qj-, q-)- 



This kind dift'ers from R. temporurla in a few points, viz. : — 



1 . It has a jirenasal rostrum. 



2. No septo-maxillaries. 



3. The supra-stapedial is confluent with the " tegmen." 



4. The inter-stapedial is not distinct. 



5. The stylo-hyal is confluent with the ear-capsule, 



6. It has a crested dentary. 



7. Quadrate partly ossified. 



9. Rana cyanophJyctis. — Male ; if inch long.''' Ceylon. 



This is another smaller kind of Indian Frog ; it is, according to Dr. GiiNTUER (ibid., 



» Dr. GiJNTHEE ("Reptiles of British India") gives the followinfir measurements (from snout to vent) 

 of the largest fpecimeiis known to him of the Indian species of I^ana here to be described :— a. Ji. Kuhh, 

 4^ inches; b. B. hea-adadyla, 51 inches; c. E. cyanophhjclk, H to 2i inches; d. B. tljrliia, 6 to 7 inches; 

 e. B. gracing, IJ inch. B. pygmma (see Gckther, P. Z. S., 1875, p. 568) measures (adult female with 

 ripe "ova") only,25 millims. long', or one inch. 



MDCCCLXXXI. G 



