e 
154 MILAX SOWERBII. 
The MANDIBLE or jaw is of areuate form and deep 
amber colour, and the chitinons continuation which 
extends over the upper surface of the mouth cavity is in 
this species well marked and distinctly striated ; the line 
of bedding within the tissues of the head is marked with hie te — teaniote 
a dark line; the median beak or rostrum is distinct, jaw of M. sowerbii, x 12. 
prominent, and somewhat pointed. 
The LINGUAL MEMBRANE has the teeth not so compactly arranged as in Milax 
gagates, and the individual teeth are broader, though displaying the same distinetly 
tricuspid median and inner lateral teeth ; the endocone, however, becomes gradually 
lost as the margins are approached, and the marginals are simply aculeate, thoug 
some show a distinct tendency to ectoconic bifurcation. 
“AQ ap? 
Fic. 177.—Representative denticles from a transverse row of the lingual teeth of J7. sowerdiz, x 180. 
The animal collected at Dundrum, Ireland, by Dr. Scharff, and the palate prepared by Mr. W. Moss. 
The formula of a Dundrum specimen, collected by Dr. Scharff, was 
eo tpt gt Pt zh x 105=8,715. 
Reproduction and Development.—The conjugation of MV. sowerbii, 
though probably occurring throughout the year, is 
more frequently observed during the colder months. 
The operation, as in M/. gagates, is very prolonged, 
usually occupying three to four hours, and Mr. 
Kew observed one instance in which the union 
extended over the space of seventeen hours. ‘The 
act is consummated by the mutual transference Fic. 178.—Spermatheca of 
of the elaborate spermatophores, the smooth, recone rgd ac 
attenuated end of which enters the spermatheca _ presence of the spermatophore 
first,! and fills and deflects the narrowed prolonga- ""8** 
tion of that organ, sometimes so abruptly as to rupture its moorings to 
the oviduct ; occasionally a second pairing may take place at so short an 
interval that a second spermatophore may become lodged in the sperma- 
theca before the disintegration of the first has taken place.* 
The eggs, which are comparatively large, being about five mill. in their 
longest diameter, are deposited in clusters of a dozen or more in the soil; 
they are oval in shape, soft and elastic, of a golden-brown colour, and 
possessing a coriaceous white freckled though translucent envelope, which 
when placed in spirit changes to an opaque white. ‘lhe progress of their 
development and the later history has not been observed. 
Food and Habits.—Milix sowerhii is subterranean and gregarious in 
habit, being often found during the day huddled together in worm-holes 
several inches below the surface; it also hides at the roots of plants, 
amongst decaying vegetation, in crevices of old walls, under stones, etc., 
coming forth during wet weather or at night-fall and retiring at daybreak 
to the subterranean retreats, into which bits of stalks are frequently dragged 
to feed on at leisure. It is usually not of common occurrence in the open 
country, but is in places one of the most abundant garden slugs, pre- 
ferring soil of a stiff clayey character, owing to its better retention of 
moisture and the greater prevalence of worm-burrows therein. It is very 
1 Monog. i., p. 376, ff. 700, 701. 2 Monog. i., p. 374, f. 691, 
