MILAX SOWERBII. 155 
destructive to bulbs and tubers and also to flowering plants of many 
kinds; it will devour fresh or decaying fungi, partially decayed cabbages 
and other vegetables or fruit, and even carrion does not come amiss. 
Its diet is, however, not restricted to such pabulum, as it is also actively 
predatory, and will attack and devour live worms, slugs, and even smaller 
or weaker individuals of its own kind, though amply provided with suit- 
able vegetable food. In captivity Mr. Gain offered it 196 varieties of 
food, 152 of which were more or less nibbled, while 74, however, were quite 
readily taken, though only potato, carrot, and Boletus edulis were eagerly 
devoured. 
The animal is of quite inactive habits, crawling slowly, often resting, 
and when doing so, or when touched or disturbed, withdrawing its head 
beneath the mantle and shrinking to about half its length, contracting 
itself almost into a semicircle; when thus contracted the keel becomes 
sinuous and parts of the body appear indented as though injured at those 
points. 
Its tenacious mucus enables it, especially when young, to readily form 
mucus threads for the purpose of descending to the ground or to a lower 
level, although during the operation the ordinary crawling position of the 
body is not maintained, but becomes so much twisted that the dorsal and 
ventral surfaces of the body may be presented to view together. 
The body slime may also at times cause the adherence of particles of 
earth to the skin, and the animal then closely resembles a lump of earth, 
assimilating thus to the ground upon which it rests. 
Fossil.—M. sowerbii is cited by Jeffreys as an Upper Tertiary fossil, 
but the record was probably based on an erroneous identification ; it has, 
however, been definitely reported from the Holocene deposits at Maid- 
stone, East Kent, by Kennard & Woodward, and found by Mr. A. 8. 
Kennard at the base of a rainwash deposit associated with bone fragments 
and Roman pottery, on the site of Roman buildings at Darenth in 
West Kent. 
Parasites.—Like M. gagates, it is very liable to be infested with an 
Acarus, probably the Philodromus limacum, these in some cases being so 
numerous as probably to cause some inconvenience to their host. 
Variation.—Milax sowerbii has been observed to vary in its external 
colouration from pure white, through yellow, grey, or brown, to an almost 
uniformly black colour. 
Generally speaking, this species is not a very variable one, and the 
modifications that take place seem to be mainly due in the darker varieties 
to the increase or diffusion of the black pigment, and in the paler forms to 
its more or less complete suppression. 
This pigmentation may also be more or less restricted in the area 
occupied, and become correspondingly intensified, as in the var. bicolor, in 
which the coloration becomes greatly enriched. 
The Sicilian variety oretea is remarkable for the development of a 
longitudinal median zone of black pigment on the shield, a feature not 
previously remarked in the species. 
The M. marginatus var. fulva of Paulucei is, according to Lessona & 
Pollonera, merely a juvenile form of AZ. carinata. 
VARIATIONS IN COLOUR AND MARKINGS OF ANIMAL. 
Var. alba Taylor. 
ANIMAL entirely white. 
Pembroke—Tenby, A. G. Stubbs. 
