C "AI>. XII. 
AMPHIBIANS. 
25 
"’ith muscles, and therefore cannot be used for loco- 
motion. As during the season of courtship it becomes 
0< % e d with bright colours, it serves, there can hardly 
30 a doubt, as a masculine ornament. In many species 
the body presents strongly contrasted, though lurid 
tints ; and these become more vivid during the 
J 1 ' ee di ng-season. The male, for instance, of our com- 
mon little newt ( Triton pundatus ) is “ brownish-grey 
c a hove, passing into yellow beneath, which in the 
K s I»ing becomes a rich bright orange, marked every- 
1 "’here with round dark spots.” The edge of the crest 
a 80 is then tipped with bright red or violet. The 
eia ale is usually of a yellowish-brown colour with 
scattered brown dots; and the lower surface is often 
c bute plain . 39 The young are obscurely tinted. The 
0Va are fertilised during the act of deposition and 
are n °t subsequently tended by either parent. We 
“my therefore conclude that the males acquired their 
i°ngly- mar kcd colours and ornamental appendages 
l0 Ugh sexual selection ; these being transmitted either 
Ue male offspring alone or to both sexes. 
^ Q ^ nuTa 01 Batrachia . — With many frogs and toads 
^ 6 colours evidently serve as a protection, such as 
6 bright green tints of tree-frogs and the obscure 
1 fled shades of many terrestrial species. The most 
tp k’Cuously coloured toad which I ever saw, namely 
0 j. e ^ lr ynisGus nigricans , 10 had the whole upper surface 
an l * e k° c ly as black as ink, with the soles of the feet 
v . ? ai '^ s the abdomen spotted with the brightest 
gra U 10n ’ ^ crawled about the bare sandy or open 
‘ s y plains of La Plata under a scorching sun, and 
« ib id. p. 146, 151. 
Mr ,° olo §y of the Voyage of the “ Beagle,” ’ 1843. “ Reptiles, ” by 
' ■ Deu > p. 49. 
