PULMONATA, 11 



The head is protruded far beyond the mouth ; the eye-peduncles 

 are long, slender, and graceful. The mouth is changed from an 

 oval to an elongated form, with parallel sides and rounded ends. 

 The glands are lengthened, lose their prominence, and appear 

 nearly smooth. But when alarmed by the touch of a foreign 

 substance, an instant change occurs, and a sudden contraction 

 takes place. The tentacles are retracted and the head is drawn 

 under the mantle. The anterior edge of the mantle is brought 

 to the level of the foot, and its form becomes nearly circular. 

 The body is shortened to one-fourth of its former length, and 

 tumid ; the back is rounded and rises high in the centre, and the 

 skin is rough with prominent glandular protuberances. The 

 carina, when it exists, becomes conspicuous. This is the form 

 which they assume iu their retreats when they retire to protect 

 themselves from the effects of drought and cold. It differs so 

 much from their form when in motion, that one not well ac- 

 quainted with them would hardly recognize the same animal in 

 its new shape. It is among the Limaces, perhaps, that the 

 change is most striking, and the difference of form between the 

 extremes the greatest. 



They commence reproducing their kind as early as the end of 

 the first year, before they have attained their full dimensions, 

 and hence the eggs of the same species often vary considerably 

 in size. These are deposited in a cluster of thirty, or thereabouts, 

 in the soil and in other moist and protected situations ; or if the 

 species be one that frequents houses, then in the crevices or 

 corners of the walls or under the decaying planks of cellars. In 

 general form and appearance they resemble the eggs of the shell- 

 bearing genera, but differ from them in several important par- 

 ticulars. The eggs of the snails are all opaque, while those of the 

 slugs are more or less transparent, permitting, in the Limaces, a 

 view of the cicatricula, and affording an opportunity of observing 

 its developments. Those of the former are all deposited free, or 

 unconnected, except by a slight agglutination ; those of the latter, 

 in some of the species, are connected together by a prolongation 

 of the outer membrane at their longest diameter, thus forming a 

 sort of rosary. The deposits of eggs, when made, are abandoned 

 by the slug, who then removes to some other convenient place. 

 A considerable number of separate deposits are made during the 

 year. 



