340 Studies in the Theory of Descent. 



species of which have I been able to experiment, 

 viz., jD. Galii and Euphorbia, 



The first of these was constantly rejected. Two 

 large caterpillars, one of the black and the other 

 of the yellow variety, were left for twelve hours in 

 the lizard vivarium, without being either examined 

 or touched. It thus appears that D. Galii is a 

 distasteful morsel to lizards ; and the habits of the 

 caterpillar are quite in accordance with this, since 

 it does not conceal itself, but rests fully exposed 

 by day on a stem, so that it can scarcely escape 

 being detected. It is almost as conspicuous as 

 D. Euphorbia. 



I was much surprised to find, however, that this 

 last species was not rejected by lizards. On placing 

 a large caterpillar, six to seven centimeters long, 

 in the vivarium, the lizard immediately commenced 

 to watch it, and as soon as it began to crawl 

 about, seized it by the head, and, after shaking it 

 violently, commenced to swallow it. In spite of 

 its vigorous twisting and turning, the insect 

 gradually began to disappear, amidst repeated 

 shakings ; and in less than five minutes was 

 completely swallowed. 13 With regard to lizards, 

 therefore, the prominent ring-spots of this larva 

 are not effective as a means of alarm, nor are they 

 considered as a sign of distastefulness. 



18 These experiments, as already mentioned above, were not 

 made with the common German lizard (Lacerta Stirpium\ but 

 with the large South European Lacerta Viridis. 



