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YERTEBRATA. 
OKDER 1. ANURA. 
The animals of this order, the name of which signifies tailless^ have a short, squat body, four 
legs, the hinder ones the longest, a large mouth ; the skin naked and extremely dilatable, in some 
cases furnished with glands which secrete an acrid liquid ; the eyes large and prominent ; 
the upper jaw usually armed with small hooked teeth ; the tongue, though sometimes wanting, 
generally of large size ; the spinal column short, consisting, as a general rule, of eight verte- 
br83. The habits are various, many living habitually in the water, while others only visit that 
element for depositing their ova, which give origin to tadpoles, the development of which we 
shall hereafter notice. We shall describe these animals imder three heads : Ranid^, or Frogs, 
BuF0NiDJ3, or Toads, and Pipid^, or Sitrinam Toads. 
THE COMMON FEOG. 
THE EAI^ID^. 
The Frogs form the highest group of the Batrachian class. They are active creatures, feeding 
on insects and Avorms. Those which live upon the ground in the neighborhood of standing 
water, and pass a considerable portion of their lives in the water, have their toes pointed, and 
those of the hinder feet united, almost to the tips, by a membrane. 
Genus RAN A: Rana. — This includes the Common Frog of Europe, R. temporaria, a very 
abundant and well-known animal. It is constantly to be found hopping about in the neighbor- 
hood of water, especially in damp evenings. It generally deposits its eggs in the water in the 
month of March ; they are enveloped in a mass of gelatinous matter, within which the eggs are 
seen gradually to increase in size for a month or five weeks, at the end of which time the young 
tadpoles may be seen moving. When ready to enter upon their aquatic existence, they eat their 
way through the surrounding jelly, and thus escape. In the course of six or eight weeks the 
four legs are fully formed ; the tail then gradually disappears, and the young frog usually quits 
the water immediately. In this way they often suddenly make their appearance in prodigious 
numbers in particular spots, giving rise to the popular superstition of "frog rains ;" and in some 
cases it is said that the little creatures have been taken up and carried to a distance by high 
winds, to the great astonishment of the inhabitants of the districts in which they afterward 
descended. 
The production of the young of these animals is so curious as to require a more detailed 
description. The ova of the female are deposited in a jelly-like mass at the bottom of the water, 
being impregnated by the male at the time of their passage. The development of the young is 
