184 
ANIMAL CURIOSITIES 
to lay nearly eight hundred eggs.” When 
descending to the ground from a shrub or 
branch of a tree, some of the Limacidce lower 
themselves by means of a slimy secretion at 
the end of the tail, the substance being dis¬ 
charged in the form of a long thread which 
quickly hardens upon exposure to the air, and 
enables the creature to support its weight 
thereby. 
The black slug {Avion empiricorum) is 
another common species found in this 
country. In spite of its name, however, it 
is not always black in colour, for reddish, 
brown, yellow, green and white specimens 
are frequently to be met with, even in the 
same locality. It subsists chiefly upon vege¬ 
table matter, but has been known to eat 
earthworms and also the dead bodies of its 
own kind. 
In the family Testacellidce , or shelled slugs, 
we have a group in which the majority are 
provided with a shell. In many instances this 
covering is of sufficient size to enable the 
creatures to conceal themselves inside, but in 
others it is very small and situated upon the 
hinder end of the elongated body. The car¬ 
nivorous slug (Testacella halistidea) burrows 
underground to a depth of several feet, pursuing 
the earthworms upon which it chiefly feeds, 
