SLUGS. 79 
of the slime exuded from the body, is a feat that 
most slugs can perform. Certainly the other 
species, as L. agrestis, L. Sowerbii, &e., do not 
appear to possess the same facility, and are more 
reluctant in resorting to this expedient for 
escaping from places they have no liking for ; 
they, however, may be forced to use this means 
for conveying themselves in safety to the ground 
by leaving them on an evergreen or other tree 
which may not be congenial to their tastes, when 
they will speedily effect their escape im this 
manner. 
The thread spun by L. arborwm is not stouter 
than a cobweb, and is of a uniform thickness, 
except close to the body, where it is sensibly 
thicker. The slug can climb up its suspended 
thread; in doing which, the head is curved up- 
wards and inwards until it touches the hinder 
portion of the body; the animal then takes the 
thread and advances with great facility. 
It has been observed at Sandown, Isle of 
Wight; Connor cliffs, Dingle; Nottingham, pre- 
ferring walnut trees; Thirsk, at an elevation of 
900 feet; Gloucestershire. 
Limax Sowzrpiu—(the Keeled Slug) (Pl. V., 
fig. 35).—This and the following species are 
readily distinguished among the Limaces, by 
the back being keeled throughout its whole 
length, and by the finely granulated shield. 
