very common about the coasts of Marseilles, gene¬ 
rally lying concealed beneath rocks or stones, mov¬ 
ing in a slower manner than even the common gar¬ 
den slug, and feeding on very small testacea, &c. 
When disturbed or bandied it discharges from its 
pores a purple juice, discolouring the water to some 
small distance round. It is supposed to be a prolific 
animal, and the young are said to arrive at their full 
size in the space of two months at farthest. 
