1 82 THE SCOTTISH NATURALIST 



INFER TEBRA TES. 



MOLLUSCA. 



4. Only one representative of the Mollusca the Great Slug 

 {Limax maximus, Linnaeus) was discovered, but that in consider- 

 able numbers, and at various stages of growth. The Slugs, curiously 

 enough, appeared to be aggregated in one particular section of the 

 pit in the four years' old incline leading off the horse-road of 

 No. 13 pit. Here as many as two dozen at a time have been 

 observed, although in other parts of the workings none were to be 

 seen, with the exception of a single specimen recorded from the 

 horse-road itself about 90 yards away. This was no doubt a 

 wanderer from the centre of dispersal in the incline. In their 

 confined area the Slugs were widely spread. They occurred on 

 the pit-props, on the moist walls of the incline, on the coal, and on 

 the "pavement" or rock-bottom whence the coal seam had been 

 removed. In normal conditions Limax maximus "frequents 

 gardens, damp and shady hedgerows and woods, hiding during the 

 day beneath stones, under fallen trees, or other obscure and damp 

 places; it, however, exhibits a decided preference for the vicinity 

 of human habitations, and readily takes up its abode in damp cellars 

 or outbuildings." l The general similarity between the present 

 situation and damp cellarage is obvious, but I know of no previous 

 records from coal-mines. That the Slug had accommodated 

 itself to its surroundings and was breeding in the darkness was 

 apparent from its numbers and their aggregation, as well as from 

 the fact that individuals of all sizes were found. 



As regards colour and markings there is little to be noted. 

 Adult specimens agreed in markings with var. sylvatica, but were 

 even darker in colour. In young specimens the colour was much 

 paler a buff yellow tinged with pink and the dark bands, 

 particularly the dorsal pair, were broken into short, irregular 

 sections. In all, the eyes had attained their normal development 

 so far as external appearance indicated. 



These molluscan specimens first drew our attention to the fauna 

 of the coal-pit, and allowing that they were there well established, 

 I had some difficulty in accounting for their food supply. Taylor 

 {op. cit., p. 38) states that Limax maximus, according to Simroth, 

 as a rule refused plants containing chlorophyll, and further that it 

 "greedily devours fungi, which, indeed, are said to form its staple 

 diet, and to be preferred to other food." On this account 



1 Taylor, British Land and Freshwater Mollusca x vol. ii., 1907, p. 36, 



