336 SUPPLEMENT 
state, that they eat more, and consequently occasion more 
mischief. In proportion as the autumn approaches they eat 
less and less, until at last they bury themselves in some exca- 
vation, and fall into a state of torpor. 
Towards the end of spring these animals seek each othe 
for the purposes of reproduction. The duration of the inter- 
course is almost two hours. 
The rut of these animals continues for a very long time, 
and it is said that they can reproduce again at the end of six 
weeks. It appears that even fecundation does not take place 
until the third time of intercourse. 
The helix has one organ peculiar to itself, which must not 
be passed over here. It would be difficult to say to what 
apparatus it properly belongs. It is formed by a purse or 
pouch, more or less elongated, obtuse, rounded at its pos- 
terior extremity, and the parietes of which are very thick 
and muscular. Its interior is a cavity of no great extent, 
with four furrows, and at the bottom is a nipple. It ter- 
minates in the cloaca by a narrow orifice above the origin 
of the female apparatus. The interior of this pouch, espe- 
cially the nipple, excretes a cretaceous matter, which being 
disposed in strata in the cavity of the pouch, assumes its 
form and produces a sort of pointed and quadrangular dart, 
with a very narrow canal in its interior. The animal has the 
power of shooting forth this dart, which is an invariable pre- 
liminary to sexual intercourse. 
If a helix be opened a little time after this intercourse, the 
male organ will be found diminished in volume, the multifid 
vesicles empty, and the pouch no longer containing the dart 
above mentioned, which, according to the observation of 
Swammerdam, is sometimes contained in the canal of the 
bladder. The ramifications of the oviduct in the interior of 
the ovary contain a fluid in which are swimming some little 
round membranes marked with a black point, which are eggs. 
