32 



THE COMMON FROG. 



[chap. 



\ 



young; but nothing of the kind exists amongst birds 

 or reptiles. In fishes , however, the male of the Httle 

 Sea-horse {^Hippocampus) is provided with a ventral 

 pouch in which the eggs are sheltered, and the same 

 class presents us with a mode of carrying the eggs 

 still more bizarre than that of Alytes obstetricans 

 just related. In the fish Arius fissiis the male 

 actually carries about the ova in the mouth, protected 

 by the jaws, till relieved of the inconvenience by 

 the hatching of the young fry. 



A South African Toad {DactyletJira capensis) is 

 interesting, as we shall hereafter see, on account of 

 certain anatomical points in which it agrees with 

 Pipa, and differs from all other Anoura. No in- 

 teresting facts, however, are known as to its habits. 



Another noteworthy form is the Mexican Rhino- 

 phryuits dorsalis, the exceptional characters of which 

 are the tongue, which is free in front instead of 

 behind, and the enormous spur-like tarsal tubercle. 



Fig. 13. — R hitiofiJiry 71US dorsalis. 



Almost all frogs and toads pass the first stages 

 •of their existence in water, going through a ivQ^, 



