300 CLASS AMPHIBIA. 



lungs as well as by its gills. At the metamorphosis the gill 

 slits close and the animal becomes wholly air-breathing. 



The Amphibia frequently live in water only during larval 

 life. As terrestrial animals in the adult state they usually 

 choose damp shady places near water, since the cutaneous 

 respiration necessitates a moist atmosphere. The food almost 

 always consists of insects and worms, but in larval life vegetable 

 matters form a considerable part of it. The Amphibia can live 

 for months without food, and many of them hibernate buried 

 in the mud, and in hot countries aestivate. They are cold- 

 blooded ; and resist a considerable amount of cold, even frost ; but 

 if the whole body is frozen they do not recover. The power of 

 regenerating lost parts is considerable, e.g. lost or mutilated 

 limbs. This power is greater in young than in old individuals. 



Distribution. The Anura are almost cosmopolitan. They 

 are represented by one species only (Liopelma) in New Zealand 

 and are absent in most Oceanic islands ; the latter fact being 

 due to the fatal effect of salt water, especially upon the larvae. 

 The Urodela are mainly Nearctic and Palaearctic, and the 

 Gymnophiona are confined to the Neotropical, Ethiopian and 

 Oriental regions. 



Urodela and Anura are not found fossil until the Eocene, 

 Gymnophiona are unknown in the fossil state. 



Order 1. GYMNOPHIONA.* APODA. 



Vermiform Amphibia without limbs or limb-girdles, with 

 biconcave vertebrae, and usually with numerous small scales em- 

 bedded in the skin. The tail is short or absent, the /rentals are 

 distinct from the parietals and the palatines are fused with the 

 maxillaries. 



The body is covered with a smooth, slimy, transversely ringed 

 skin, which contains in the cutis numerous small calcified scales 



* J. Miiller, Ueb. d. Kiemenlocher der jungen Coecilia, Mutter's 

 Arch. 1835. R. Wiedersheim, Die Anatomie der Gymnophiona, Jena, 

 1879. G. A. Boulenger, op. cit. and P.Z.S. 1895, p. 401. P. and F. 

 Sarasin, " Zur Entwick. u. Anat. der Ichthyophis glutinosus" Ergeb. 

 naturwiss. Forsch. auf Ceylon, 1887. R. Burckhardt, " Him u. Geruchs- 

 organ von Triton and Ichthyophis" Z. /. w. Z. 52, 1891 p. 370. J. W. 

 Spengel, " Urogenitalsystem der Amphibien" Semper' 8 Arbeiten, 3, 1876, 

 p. 1. A. Brauer, Entwick u. Anat. der Gymnophionen, Zool. Jahrb.,Anat. t 

 10, 1897, p. 389, and 12, 1899, p. 477. 



