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throat-sac of the males being enlarged and modified so as to form an extensive 
chamber on the under surface of the body in which the eggs and tadpoles undergo 
their development. This chamber is entered by two apertures situated on the 
floor of the mouth on each side of the tongue; and when the eggs, generally from 
eleven to fifteen in number, are laid by the female, they are taken and swallowed 
by her consort, who passes them into his pouch. When the tadpoles are sufficiently 
developed, they enter the world by escaping through the parental mouth. It 
appears that at no stage of their existence do the tadpoles possess external gills. 
The Sharp-Nosed Frog. 
Family Gera toba tea chid be. 
Omitting detailed mention of the small and unimportant family of the 
Discophidce, characterised by the presence of teeth in the upper jaw, and the 
expansion of the extremities of the transverse processes of the sacral vertebra, our 
last representative of the first suborder is the sharp-nosed frog (Ceratobatrachus 
guentheri), of the Solomon Islands, which constitutes a family by itself. The 
essential characteristics of the family are the presence of teeth in both the upper 
and lower jaws (a feature found elsewhere only in two families of the next 
suborder), coupled with the absence of expansion of the extremities of the sacral 
vertebrae. This frog has a very large triangular head, ornamented with prominent 
ridges, and terminating in front in a pointed flap of skin; similar flaps occupying 
the eyelids, and the mouth having an enormous capacity. In the eye the pupil is 
horizontal; and teeth are present on the vomers. The hind-limbs are rather short; 
and all the toes have simple terminations, and are devoid of webs. In colour this 
curious frog is very variable. Although very little is known as to its habits, it 
appears to be abundant in the Solomon Islands; and it is remarkable for laying 
very large eggs, from which the young emerge nearly fully-developed. 
The Southern Frogs. 
Family LEPTODA CT YLIDAE. 
In the greater part of South America and the whole of Australia the typical 
frogs are replaced by a family which, for want of a better name, we may call the 
southern frogs. These, together with seven other families, differ essentially from 
the forms hitherto considered, in regard to the conformation of the bones of the 
chest, and thus collectively constitute a second suborder, known as the Arcifera. 
It will be remembered that in the preceding suborder the two metacoracoid bones 
are connected together by a single cartilage joining their free edges ; in the present 
group each metacoracoid terminates in a large cartilage, in such a manner that one 
cartilage overlaps its fellow of the opposite side. The southern frogs resemble the 
typical frogs in having the upper jaw alone toothed, and in the transverse processes 
of the sacral vertebra being cylindrical or but slightly expanded, while they also 
agree in the characters of the vertebrse and the absence of ribs. It is thus evident 
vol. v .—18 
