FROGS AND TOADS 
20 1 
Amphibia is afforded by the circumstance that 
they all pass through a transitional or larv'al 
condition before arriving at the adult state. 
The familiar tadpole phase of the common frog 
or toad typically illustrates this point. During 
its earliest larval state the fish-like resem- 
blance is especially conspicuous. In addition 
to possessing gills, the body is limbless, and 
produced into a long fish-like tail, having 
superior and inferior fin-like membranes, 
with which the little animal propels itself 
through the water. These locomotive fins, 
however, are never furnished with supporting 
fill-rays, as obtains among the Fishes. In 
contradistinction to the Lizards and Snakes, 
the skin of Amphibians is never covered with 
spines or scales, but is soft and naked. In 
many of the Toads and Salamanders the surface of the skin is, however, warted and highly 
glandular, and capable of emitting an acrid and sometimes po.sonous fluid. More or less 
pronounced conditions of moisture are essential for the well-being of all Amphibians. The 
eggs are deposited, and the earlier or larval conditions, with but few exceptions, passed, in 
the water, while the adults remain in its near proximity, and frequently take up their abode 
in it. Amphibia do not, however, drink water after the manner of lizards and other reptiles, 
but absorb all the moisture they require through the surface of their skins. The deeper 
and more essential skeletal elements of the Amphibia differ conspicuously from those of the 
preceding groups. The vertebrae in the permanently gill-bearing species more particularly 
are scarcely to be distinguished from those of fishes. In the Frog and Toad Tribe, on the 
other hand, they are reduced to a less number, seven or eight only, that is found among 
any other vertebrates, while ribs do not exist or are rudimentary and functionless throughout 
the class. Many bones of the skull in the Amphibia, as well as its general coiiotruction, are 
more in accord with those of fishes than of ordinary reptiles. The tongue, not always present, 
is attached immediately inside the front of the lower jaw, its tip pointing down the animal’s 
throat. It is remarkable that, notwithstanding their aquatic proclivities, no Amphibian has 
been discovered which frequents salt water. 
Amphibians amongst themselves constitute two very easily recognised sub-divisions, — the 
one including the Frogs and Toads, collec- 
tively forming the Tailless group; and the 
other represented by the Newts and Sala- 
manders, or Tailed Amphibians. The former 
group has an almost world-wide distribution, 
numbering some thousand species ; it is most 
abundantly represented in the tropics, rang- 
ing thence in diminishing numbers to the 
limits of the Arctic Circle. In colder climates 
these Amphibia usually hibernate during the 
winter months; while in tropical countries, 
where dry seasons intervene, they often 
bury themselves in the mud, and remain 
in a state of torpor till the return of the 
rains. The majority are more or less es- 
sentially nocturnal in their habits. Frogs 
and toads commence life in an aquatic 
Photo by IV. P. Dando, F.Z.S. 
TIGER-LIKE FROG 
zi species closely allied to the common frog, but more boldly marked 
Photo by Scholastic Photo Co, 
EDIBLE FROG 
T^e hind legs only of this species are used for the composition of the 
famous dish 
