II HABITS OF CARNIVOROUS SNAILS AND SLUGS 53 



pharynx, is a veiy remarkable feature in the habits of the ani- 

 mal. It appears, as it were, to harpoon its prey by a rapid thrust, 

 and when the victim is once pierced by a few of the powerful 

 sickle-shaped teeth (compare chap, viii.) it is slowly but surely 

 drawn into the oesophagus (Fig. 20). 



Most gardeners are entirely ignorant of the character of 

 Testacella^ and confuse it, if they happen to notice it at all, with 

 the common enemies of their tender nurslings. Cases have been 

 known, however, when an intelligent gardener has kept specimens 

 on purpose to kill worms in ferneries or conservatories. In some 

 districts these slugs are very numerous ; Lacaze-Duthiers once 

 dug 182 specimens from a good well-manured piece of ground 

 whose surface measured only ten square yards. 



Towards the end of September or beginning of October the 

 period of hibernation begins. I infer this from the behaviour of 

 specimens kept in captivity, which, for about a fortnight before 

 this time, gorged themselves inordinately on as many worms as I 

 chose to put into their box, and then suddenly refused food, 

 buried themselves deeply in .the earth, and appeared no more 

 during the winter. The eggs are apparently much less numerous 

 than is the case with Limax or Helix^ and very large, measuring 

 about ^ inch in diameter. They are enveloped in a remarkably 

 tough and elastic membrane, and, if dropped upon any hard sur- 

 face, rebound several inches, just like an india-rubber ball. 



The animal creeps rather rapidly, and has the power of 

 elongating its body to a remarkable extent. When placed on 

 the surface of the ground, in the full light of day, it soon betrays 

 uneasiness, and endeavours to creep into concealment. Its method 

 of burying itself is very interesting to watch. It first elongates 

 its neck and inserts its head into the soil ; gradually the body 

 begins to follow, while the tail tilts upwards into the air. No 

 surface motion of the skin, no writhing or wriggling motion of 

 any kind occurs ; the creature simply Avorks its way down in a 

 stealthy and mysterious way, until at last it is lost to view. 



The great Glandiiia^ which attain their maximum develop- 

 ment in Mexico and the southern United States, are a very 

 noticeable family in this group. According to Mr. Binney,^ 

 Grlandina trimcata Gmel., one of the commonest species of the 

 genus, is somewhat aquatic in its habits. It is found in the sea 

 1 Bull. Mus. Comp. Zool. Harv. iv. p. 85. 



