56 LIMAX CINEREO-NIGER. 
MANDIBLE or jaw smaller and weaker than in Limax maximus, of a pale amber 
colour, with usually two dark submarginal parallel = 
thickenings near the upper margin ; the median beak 
projects somewhat beyond the line of jaw, but is not 
nearly so convex or so prominent as in L. maximus, 
and the lower outer angles of the jaw, so abruptly Fic. 79. Mandiblewor tawedt 
angulated and almost rectangular in L. maximus, ave — Limax cinereo-niger Wolf X 8. 
in the present species obliterated by the convexity con- (Goyt Valley, Cheshire, Mr. C. 
necting the upper and lower margins, the ends having ©!¢ham)- 
to some extent the somewhat horned aspect distinguishing the mandible of Hyalinia 
helvetica. 
The LINGUAL MEMBRANE of a Cheshire specimen is eight mill. long, and three 
mill. or more in breadth, covered with slightly curved transverse rows of teeth which 
are very uniform in size, only diminishing at the margins 3 median row with a some- 
what hour-glass shaped base, similar to that of L. maximus, and bearing a broad 
reflection with obsolete side reflections and a strong mesoconic prolongation bearing 
trifid cutting points ; lateral teeth trifid, with strong mesocone, distinet endocone, 
and a less pr rominent ectocone, which in the succeeding teeth becomes more distinct, 
“ign ouag 9 9504 
Fic. 80.—Representative denticles froma transverse row of the lingual teeth of L. c/nerveo-niger Wolf x 120. 
The animal collected by Mr. C. Oldham at Whaley Bridge ; the radula prepared by Mr. W. Moss, and 
photographed by Mr. T. W. Thornton. 
though always more basal than the endocone; about the twentieth row, the teeth, 
thouch still trifid, become more aculeate in char acter, and about the thir tieth row 
the endocone becomes obsolete, the ectocone and mesocone only being retained to 
the margins of the membrane, although a few trifid teeth may sometimes be seen, 
due, howev er, to the retention from the embryonic state of a secondary ectocone. 
The dental formula of a Whaley Bridge specimen, collected by Mr. C. Oldham, is 
444+504+1+50+44 x 168=25,032. 
28 TAS) Se 
Reproduction and Development.—Pairing would appear to take 
place throughout the milder periods of the year, and is always preceded by 
the same amatory. preludes and prolonged circular procession described 
under Limax maximus, but during the act of congress the animals do not 
invariably suspend themselves by a long conjointly secreted mucus cable, as 
in that species, but remain firmly attached to the underside of the branch 
or other object by the greater part of the sole, leaving free only the anterior 
part of the body to become entwined with that of their partner. 
‘he general character of the conjugation is, therefore, similar in the two 
species, although there are no precise modern observations available for 
comparison of the details of the act. 
he ova are deposited in moist places beneath the shelter of fallen trees, 
under loose bark, or other suitable situations, those of the var. corsica being 
described by Moquin-'andon as globular in shape, and about five mill. in 
diameter, shining, transparent, about the colour of gum-arabic, and united 
together in little clusters, and are said to hatch in about a month’s time. 
According to Lessona & Pollonera, the young when hatched have the shield 
mottled with black and white, and the foot-sole pale and unicolorous, but as 
growth proceeds, the pale markings on the shield become clouded over by the 
diffusion from the centre of the dark markings, which gradually extend 
towards the margins, which are also eventually darkened over, except in some 
adults which may retain traces of the pale maculations of their early life, but 
these vestiges are always more especially displayed towards the margins. 
The lateral zones of the sole are also little by little invaded by the dark 
tint, until they acquire their full depth of colouring, or as in the case of the 
dark colouring of the shield, the process of pigmentation may be arrested 
or retarded, and examples may therefore be found, especially at or near the 
