56 LIMAX CINEREO-NIGER. 



MANDinLE 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. maxhiitis, 

 and the lower outer angles of the jaw, so abi'uptly p,j. 79._Mandible or jaw of 

 angulated and almost rectangular in L. maximus, are Limax cinereo-ni^er^oV v. 8. 

 in the present species obliterated by the convexity con- niHh°^'7^"°^' *"'*''''''''' ^''' ^' 

 necting the upper and lower margins, the ends bavin" Oldham), 

 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 ; median row with a some- 

 what hour-glass shaped base, similar to that of L. maximus, and bearing a broad 

 reflection with obsolete side redections and a strong mesoconic prolongation beai-ing 

 trifid cutting points ; lateral teeth trifid, with strong mesocone, distinct endocone, 

 and a less prominent ectocone, which in the succeeding teeth becomes more distinct, 



Fig. 80. — Representative denticles from a transverse row of the lingual teeth of L . cinereo-niffer Wolf X 120. 

 The animal collected by Mr. C. Oldham at Whaley Bridge ; the radula prepared by Mr. W. Mo-ss, and 

 photographed by Mr. T. W. Thornton. 



though always more basal than the endocone ; about the twentieth row, the teeth, 

 though still trifid, become more acnleate in character, and about the thirtieth 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, however, to the retention from the embryonic state of a secondary ectocone. 

 The dental fornmla of a Whaley Bridge specimen; collected by Mr. C. Oldham, is 

 ^/+\»+^'+7+Y X 168=25,032. 



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. 



The 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. 



The 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-Tandon 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 



