44 MR. W. K. PARKER ON THE STRUCTURE AXD 



the orbito-sphenoidal region, and tliis gi-ows backwards as a sharp wedge, between the 

 right and left bony tracts below (fig. 12). 



The " gii-dle-bone " runs well into the true fore edge of the ethmoidal region, up to 

 the autogenous nasal roof, and outwards into the "ethmoidal wings," where they 

 pass into the palatal pedicle of the face (c.pa.). There is no "prenasal rostrum" 

 formed by the intertrabecula in front, but the pro-rhinals (p.rh.) are good-sized hooks, 

 and the upper and lower lamina; of cartilage are broad and well-developed. The out- 

 works of the nose, the two paii-s of upper labials {ii.lKu.l-.), are quite normal. 



The outer' less, and the inner more, bent arches of the face are very beautifully 

 formed ; they are strong, but not thick and solid. The palatine (pa.) and the pterygoid 

 (pg.) have affected the cartilaginous bar very little; the former is falcate, with an 

 unusual curve ; tlie latter is short, both in its process for the " pedicle " and that for 

 the quadrate region. 



The bones that form so perfect a semi-oval outline are quite normal also (px., 

 mx., q.j.) ; the hindermost or quadrato-jugal has largely infected the quadrate with bony 

 matter. The Eustachian tube (eu.) in the round notch of the pterygoid (jyg.) is a 

 short oval with its greatest diameter parallel with the axis of the skull ; it is generally 

 obUque in position (see Plates 6 and 7). 



Over the semi-osseous suspensorium the squamosal (.svy.) liinds liy a very sigmoid, 

 broadening stem : above, it is small on the tegmen tympani, but has a long, out-turned, 

 postorbital snag. It is enclothed with a large and very broad " annulus," which, 

 however, differs from the Oriental Ranee generally, but agrees with tlie English kind, 

 by being imperfect above ; its crura are unusually wide apart. 



The stapes (Plate 5, figs. 12 and 15 st.) is large, oblique, sub-uncinate behind, and 

 has a sinuous front margin. It has the intercalary inter-stapedial [i.M.) very dis- 

 tinct, large, and ovoidal ; the medio stapedial bone {m..st.) is pistol-shaped, with a very 

 large handle ; the extra-stapedial (e.st.) is small and orbicular, and its supra-stapedial 

 process (s.st.) is free above, as in Ji. teviporaria, but it is here a short rounded bud. 



Still there is in this kind a very highly developed " middle ear," and it is not in any 

 sense a low kind of Frog. 



The nasals {n.) and the fronto-parietals {f.p>.) are well-developed, but not very thick ; 

 the parasphenoid (pa.s.) is, like the skull it forms a floor to, broad and strong; it is 

 trifurcate in front, sinuous laterally, and notched twice on each side behind : has a 

 triangular " handle " at its end, and a wide rounded " guai'd " ; it nearly i-eaches the 

 foramen magnum, behind, but in front it reaches only half-way along the girdle-bone. 

 The vomers (v.) are quite normal, but very wide apart. 



The mandible (fig. 13) is perfectly normal, and doe.s not show any dentary apophysis. 



The hyo-branchial plate (fig. 14) is like that of the two last species, and differs but 

 little from that of the common kind ; the dorsal end of the hyoid band does not 

 coalesce wnth the auditory floor behind the Eustachian tiibe (fig. 12, eii., st.h.). 



As compared with that of R. tenipoyaria, this skull diflers very little in essentials. 



