BRITISH AMPHIBIANS 
to the bottom, but as the gelatinous substance with 
which they are surrounded begins to swell, and thus 
becomes lighter and more buoyant, the mass of spawn 
rises to the surface where the warmth of the sun, with 
the gracious influence of light and air, helps to complete 
the hatching process. As soon as the dark chocolate- 
coloured tadpole emerges (and the egg can easily be 
observed changing shape within the transparent jelly- 
sphere), it is the owner of external gills, and a fringed 
sucker on the under part of the head enables it for 
a time to cling to any surrounding object. In due 
course the external gills are exchanged for internal ones, 
and the sucker is discarded, there being no further use 
for it. ‘The head becomes bull-dog like, the mouth is 
formed, and the hind limbs appear. The front pair of 
limbs poke through last of all as, until they emerge, 
they remain hidden within the gill-chambers. After 
several weeks, the internal gills disappear, lungs are 
formed, and the tadpole comes to the water-surface to take 
in air. It is a vegetarian in diet up to now, but there 
comes a time when it seems to lose its appetite, and per- 
haps there is small wonder for this when one realises the 
wonderful changes taking place both within and without. 
The tail becomes shorter, the mouth widens, the lip- 
frills wither, the horny jaws disappear, the eyes pierce 
the skin, the front pair of legs poke through, and these 
things completed, the tadpole commences to feed again. 
But, meanwhile, it has ceased to be a vegetarian, indeed 
has developed the ways of a cannibal, as it will readily 
40 
