DEVELOPMENT OF THE SKULL IN THE BATRACHIA. 
41 
are un ossified; the floor is wide in front and narrower behind, whilst the contrary is 
seen in the roof. The subnasal angles are well developed; the pro-rhinals (p.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 (it.P.u.l 2 .) are well developed. The large palato-suspensorial 
arch is but little affected by the bones investing it,—the palatal and the pterygoid 
( pa.,pg .); but these are normal and well-developed; there is no metapterygoid, and 
the part above the quadrate hinge is largely ossified by the quadrato-jugal ( qq-jfl 
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-hyal 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-stapeclial bar (fig. 10, i.st.,m.st.,st.) ; 
the extra-stapedial (e.st.) is not spatulate, 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 behind the mento-Meckelian; the hyo-branchial plate (fig. 9, h.hy.) has 
a broader hypo-hyal lobe than in the Common Frog. 
The fronto-parietals (flp.) 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 
cartilage (figs. 6, 7, flp., n., px., mx., pa.s., q.j., q.). 
This kind differs from R. temporaria in a few points, viz. :—• 
1. It has a prenasal rostrum. 
2. No septo-maxillaries. 
3. The supra-stapedial is confluent with the “ teg men.” 
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. Rayia cyanophlyctis. —Male ; if inch long.* Ceylon. 
This is another smaller kind of Indian Frog; it is, according to Dr. Gunther (ibich, 
* Dr. Gunther (‘‘Reptiles of British India”) gives the following measurements (from snout to vent) 
of the largest specimens known to him of the Indian species of Sana here to be described :— a. R. Kulili, 
4g- inches; b. R. hexadactyla , 5^ inches ; c. R. cyanophlyctis, 1^ to 2| inches; d. R. tigrina, 6 to 7 inches; 
e. R. gracilis, 1|- inch. R. pygmcea (see Gunther, P. Z. S., 1875, p. 568) measures (adult female with 
ripe “ova”) only 25 millims. long, or one inch. 
MDCCCLXXXI. G 
