GENERAL CHARACTERISTICS OF BATRACHIANS. 295 
Batrachians may be briefly defined as cold-blooded vertebrate 
animals, which, as a rule, commence their life in fresh water, 
which generally possess a naked skin, and which always pass 
through a metamorphosis. Some of the Batrachians have a very 
complete metamorphosis, e.g., Frogs and Toads; others, such as 
Newts and Salamanders, not so complete. Certain of the Bat- 
rachians, for example the Surinam Toad (Pipa americana) and 
the Black Salamander (Salamandra atra), undergo their meta- 
morphosis while still within the egg. 
Batrachians are oviparous, like the Common Frog (Rana tem- 
poraria), or ovoyiviparous, like the Spotted Salamander (Sala- 
mandra maculosa). By far the greater number are, however, 
oviparous. 
The eggs of these creatures are deposited in fresh water 
either in masses, or strings, or singly, e.g., the Common 
Frog (Rana temporaria), the Common Toad (Bufo vulgaris), 
and the Smooth Newt (Molge vulgaris), respectively ; or in 
damp places, e.g., the Black Salamander (Salamandra atra) ; 
or in the axils of the leaves of trees, e.g., certain species of the 
genus JZylodes ; or they are twisted in strings round the thighs 
of the males, e.g., the Midwife Frog (Alytes obstetricans); or 
they are placed in a pouch upon the back of the female, e.y., the 
American Pouched Tree Frog (Nototrema marsupiatum); or in 
cells formed in the thickened and loose skin of the female’s back, 
e.g., the Surinam Toad (Pipa americana) ; or in the throat-sac of 
the animal, e.g., Rhinoderma darwinti; or buried in a hole in 
damp earth and protected by the female, e.g., certain of the 
Coecilians. 
Tailless Batrachians are found in nearly every part of the 
world except New Zealand and the Arctic regions: the tailed 
Batrachians are natives of Europe, Asia, and North and South 
America. Though the Batrachia are closely allied to fishes, none 
of them are dwellers in salt water. In the colder parts of the 
world the Batrachians hibernate; and in the hotter parts many 
of them estivate. 
Certain of the males of the Ecaudata are remarkable for 
their powers of making sound, often out of all proportion to 
their size. 
