174 MR. W. K. PARKER OX THE STRUCTURE AND 



The bone hardly affects the ethmoidal wing, but runs fairly up to the septum nasi 

 {■t.n.), below; above (fig. 1, eth.), it is very narrow, where it forms an arcuate margin 

 to the fontanelle. 



The nasal region is well developed, both as to roof and floor ; it is wholly cartila- 

 ginous, it is broad, but arcuate (not transverse), in front, and ends in five large, well 

 formed processes (figs. 1, 2, and 4). Each outer angle of the primary cornua trabeculae 

 (fig. 4, c.tr.), is a large, broad, decurved ear of cartilage, and the pro-rhinals (^J.^'A.), are 

 long, large, and pedate ; the prenasal {j^-"-) is spatulate, and one of the best, in shape 

 and size, to be seen in the whole group. Between this bar and the out-turned pro- 

 rhinals, the nasal-nerve openings (n.n.) are large. The palato-suspensorials are stouter 

 than in the two last ; the pterygoid and palatines {]>[/•, p/^-) are stronger even than 

 in H. Ewimjii, but the cartilage of the pedicle (pcZ.) is much less solid; that of the 

 quadrate is equal to what is seen in that species ; this latter part is not ossified. These 

 condyles have retreated to a point opposite the hind margin of the stapes ; this is 

 intermediate between what we see in the two last kinds. So, also, are the internal 

 nostrils {i.n.), they are sub-oval and oblique, but not to the same extent as in 

 //. j9/i^//oc/»'oa ; the Eustachian openings {eu.) are very similar in all three; they are 

 quite circular in this species. The external nostrils {e.n.) and the vipper labials 

 {u.l^.u.¥.) are very similar to those of ^. Eioingii. 



The annulus {ci-ty.) is impei'fect above, but it is of the average size. 



The stapes and the other linked segments of the ear-chain (fig. 5, St., i.st., m.st.) are 

 large ; the proximal segment is oval and unossified, but quite distinct from the solid 

 head of the medio-stapcdial. 



The extra-stapedial is a long, decm-ved, spatula, giving off a ligulate cartilaginous 

 supra-stapedial {e.st., s.st.), which like the stylo-hyal (s.th.) is confluent above. 



The rest of the hyoid band (fig. 3, c.hi/.) is rather broad; it lessens before it turns 

 back, has no lobe, and soon melts into the basal plate. 



That plate {h.lb.hr.) is extremely small, both foi-e and aft, and has inordinately large 

 thyro-hyals {t.hy.) : its lateral lobes are but little pronounced, especially on the right 

 side. The mandible (fig. 3, m.mh., d., ar.) is normal. 



The investing bones are somewhat denser than in the small Australian Hi/lw ; the 

 fronto-parietals {f.}^.) are only one-third as long as the skull, and overlap tlie marginal 

 "tegmen"very little; they are small, straight, and gently conchoidal, with only a 

 slight temporal dilatation. 



The nasals (fig. 1, v.) are fine large stalked crescentic shells of bone, coming very 

 near each other at their inner edge ; these bones, and the pre-maxillaries, septo- 

 maxillaries, maxillaries, quadrato-j ugals, and squamosals, are all similar to what would 

 be found in a young Common Frog of the same size as the adult of this species. 



The parasphenoid and vomers (fig. 2, pa.s., v.) are normal and large ; the former has 

 its wings pointed, and not dilated, and the latter are thrown wide apart by the 

 dilatation of the basi-nasal tract. 



