124 URODELA chap. 



body, it is then slipped backwai'ds- over the trunk and tail, 

 whereupon the newt seizes the skin with the mouth, draws the 

 shirt off entirely, and — swallows it. Such freshly shed skins are 

 very delicate and pretty objects when suspended in water ur 

 some preserving fluid. The shed skin, consisting only of the 

 outermost layer of the epidermis, is entire, but turned inside out, 

 with lingers and toes complete, the only holes being those for 

 the mouth, eyes, and vent. 



Xone of the Tritons are viviparous. The eggs, which are 

 glued singly or in small numbers on to stones or water- 

 plants, are hatched in about a fortnight, sooner or later accord- 

 ing to the species and the prevailing temperature. The larvae 

 are always provided with three pairs of branched external gills ; 

 the fore-limbs appear much earlier than the hind-limbs. Most, 

 perhaps all, larvae develop two pairs of thread-like protuberances 

 on the sides of the upper jaw, by means of which they attach 

 or anchor themselves on to water-plants shortly after they are 

 hatched. Thus moored they remain motionless in a slanting 

 position, now and then wriggling their tails and shifting their 

 place, or sinking to the bottom. The metamorphosis is finished 

 during the first summer, and the little newts, often partially 

 transparent, leave the water to hide under stones. Not unfre- 

 ij[uently the metamorphosis is retarded and not finished by the 

 autumn. Tlie larvae of T. cristatus, especially when reared in 

 ponds with abrupt or overhanging banks, so that they cannot 

 leave the water, retain considerable remnants of the gills, still 

 more frequently the clefts, although breathing chiefly by the 

 lungs. Such individuals reach a length of 3 inches, and are 

 larvae so far as the finny tail and the gills are concerned. They 

 liibernate in this condition, and in exceptional cases reach sexual 

 maturity ; — at least the females, wliich develop ripe eggs ; the 

 males are not known to produce spermatozoa. 



Much has been written on the amorous games of newts, 

 but it is only recently that the mode of fecundation has been 

 actually observed. Gasco ^ placed the newts in glass vessels 

 suspended from the ceiling of his laboratory. The antics of the 

 enamoured male around the female, rubbing the latter with its 

 head, or lashing it gently with the tail, and playing around it 

 in its often beautiful nu])tial dress, are meant to excite the 

 ' Ann. Mils. Ocnova, xvi. 1880, \). 83. 



