SALAMANDRINAE I I 9 



places provided with moss, rotten stumps and stones, to . afford 

 tliem suitable moist and cool hiding-places, and they readily take 

 earthworms, larvae of beetles, snails, woodlice, etc. But any 

 attempt to keep them in large numbers ends in failure. They con- 

 gregate together in clumps, all making for the same cavity or recess, 

 as if that were the only one in existence (very likely they are 

 right in so far as that place is probably the- best), and they get 

 rapidly enlarging sores, chiefly on the elbows and knees. These are 

 soon infested with fungoid growths, and this disease spreads 

 like an epidemic and soon carries them off. 



S. atra. — The Alpine Salamander differs from the Spotted 

 Salamander by its uniform black colour and smaller size, which 

 averages between 7 and 5 inches. It is restricted to the Alps 

 of Europe, from Savoy to Carinthia, at from 2000 to as much 

 as 9000 feet, elevation, living with predilection near waterfalls, 

 the spray of which keeps the neighbourhood moist, or in mossy 

 walls, in the shade of forests near brooks, or under flat stones on 

 northern slopes. The most interesting feature of this species 

 is that it produces only two young at a time. These are 

 nourished at the expense of the partially developed eggs in the 

 uterus, and they undergo their whole metamorphosis before 

 they are born. By far the best and most complete account 

 of this mode of propagation has been given by G. Schwalbe.' 

 The length of the ripe embryos is about 45 mm. ; they lie 

 mostly bent up, with their heads and tails turned towards the 

 head of the mother. The gills are beautiful, delicate red organs, 

 the first pair being generally directed forwards and ventralwards, 

 the second upwards, the third backwards ; they are longest 

 when the creature is about 32 mm. long, while there is still 

 much yolk present. At this stage the gills are so long as to 

 envelop nearly the whole embryo. There is rarely a second 

 embryo in the same uterus, and an extra foetus is generally 

 smaller, frequently a monstrosity not fit to live ; it is probable 

 that it is not used as food, but that it is expelled at parturition. 

 The embryo passes through three stages, (1) still enclosed within 

 its follicle and living on its own yolk, (2) free within the 

 vitelline mass which is the product of the other eggs, (3) there 

 is no more vitelline mass, but the embryo is possessed of 

 gills 10-12 mm. in length, and is still growing. During the 



1 Zeitschr. Biol, .\xxiv. 1896, pp. 340-396. 



