284 
FROGS AND TO A FS. 
Other Genera. 
months these have completed their development and leave the water. W hen an 
adult toad-frog is suddenly seized or pinched, it utters a cry like the mewing of a 
kitten, at the same time emitting a pungent vapour with a strong odour of garlic, 
both these being apparently intended as a means of defence. 
Of the remaining genera, Pelodytes, as represented by the 
punctured toad-frog (P. punctatus ) of Western Europe, and the 
Papuan Batrachopsis, differ from the preceding in that the sacral vertebra 
has two condyles for articulation with the rod forming the termination of the back¬ 
bone, the hind-toes being slightly webbed. In the Oriental genus Leptobrachium, 
there is but a single condyle for the articulation of the rod-like bone. 
Allied In the Miocene rocks of Europe there occur remains of numerous 
Extinct Frogs, frogs which are assigned to an extinct genus, Pcdceobatraclius, regarded 
as representing a family ( Pcdceobatrachidce ) connecting the present one with the 
under-mentioned Xenopodidce. In these extinct forms the upper jaw is toothed, 
the transverse processes of the sacral vertebra have expanded extremities; the 
sacral vertebra articulates with the terminal rod of the backbone by means of two 
condyles; the vertebrae have their articular cup in front; and there are no ribs. 
The Disc-Tongued Frogs. 
Family PiSCOGLOSSID je. 
The disc-tongued frogs, as the members of this group may be called, form a 
small family represented by four genera and seven species, inhabiting the northern 
half of the Old World and New Zealand. As a family, these frogs are characterised 
by the presence of teeth in the upper jaw, the expansion of the processes of the 
sacral vertebra, the presence of short rudimentary ribs, and the circumstance that 
in the bodies of the vertebrae the articular cup is placed at the hinder-end, and the 
ball in front. In both the latter respects these frogs resemble the salamanders and 
newts, and they may accordingly be regarded as some of the least specialised repre¬ 
sentatives of the order. Their remains occur abundantly in the middle Tertiary 
rocks of Europe. The family derives its name from the disc-like form of the 
tongue, which may be either free or adherent. From all the forms hitherto described, 
the tadpoles, after shedding the external gills, differ in having the breathing-pore 
situated in the middle of the under surface of the body, instead of on the left side. 
Fire-Bellied From the painted frog (Discoglossus pictus) of Southern Europe 
Frog ‘ and North-Western Africa, which alone represents the typical genus 
of the family, the fire - bellied frog ( Bombinator igneus ), represented in the 
figure on p. 257, is distinguished by the absence of an external tympanic mem¬ 
brane to the ear; while it is further characterised by the adherent tongue, the 
triangular form of the pupil of the eye, and the great expansion of the extremities 
of the transverse processes of the sacral vertebra. This frog, which inhabits 
Europe and Asia, although unknown in the British Islands, has the skin very warty 
on the upper-parts, while beneath it is nearly smooth. In colour it is olive above, 
With or without black marblings; while beneath it is orange or yellow, marbled 
with black. The males are devoid of a vocal sac, but during; the breeding-season 
