244 riiocEEniNos of the malacological society. 



and the Carpathiaus, and, aceordinp; to Murch, near Holstcnborp; in 

 Denmark. In a fossil state it has only been recorded from the Middle 

 Pleistocene of Leuben near Lommatzsch, and Robschiitz near Dresden, 

 and from the Upper Pleistocene of Weimar. Four examples have 

 rewarded Mr. Abbott's labours, two of which are immature. 



Helix nemoralis, Linn. The examples of this species are very fine, 

 and exhibit those ditf ercnccs of coloration observable in recent examples. 

 Several of the immature individuals had an open umbilicus, and in one 

 instance this had persisted in the adult. 



Carychinm minimum^ Miill. Two examples of this species difPer so 

 much from the type as to merit extended notice. They are much 

 more slender in form, not exceeding -75 mm. in width, but being quite 

 2 mm. in height. The whorls are six in ninuber, more closely coiled, 

 and consequently longer, and increase more gradually all through, so 



Cariirhium minlmnm, IMiill., var. x 12. 



that the spire is higher and more tapering. The body- whorl is 

 much less in proportion. The moTith is more rounded and not con- 

 stricted at the outer tooth ; on the other hand, the tootli itself is greatly 

 reduced, and is represented by a mere thickening of the labriim. The 

 columella-teeth are not more than one-tliird the size of those in recent 

 examples, and occur far back inside the whorl, so as to be invisible 

 when the shell is viewed obli(j[uely. The peristome is more reflected 

 and less thickened. 



Limax maximus and Claiisilia laminata are new records for the 

 Pleistocene of this country, besides those already mentioned. 



TInio is only represented by small fragments far too minute for 

 specific determination. 



Considerable ditference of opinion still exists as to the true age of 

 the Ightham fissure, and unfortunately the mollusca throw but little 

 light on the question. That it is Pleistocene, is shown by the presence 

 of Hygromia timhrosa and Succmea ohlonga, as well as by the absence of 

 all characteristic Holocene shells ; but, at the same time, the almost 

 total absence of fresh-water forms precludes a comparison with other 

 Pleistocene deposits, in which the latter are so abundant. This 

 absence of fresh-water mollusca has been used as an argument against 

 the fluviatile origin of the contents of the fissure ; it is noteworthy, 

 however, that the stream flowing through tlie valley in which it is 

 situate contains no mollusca. 



Taken altogether, the shells from our cave-deposits are decidedly 

 larger than recent examples ; and there can be no doubt that there has 

 been a marked diminution in the size of our indigenous mollusca, and 

 probably also in their numbers, since Pleistocene times. 



