ZOOLOGY 



MOLLUSCS 



The soil of Nottinghamshire is not as a whole favourable to the de- 

 velopment of molluscan life, the bed-rock of the greater portion being 

 sandstone, while the drifts that cover it are not particularly rich in car- 

 bonate of lime. Along the western borders of the county, however, 

 where the Permian limestones occur, the land-snails are abundant ; 

 whilst the streams everywhere, and especially the canals, are rich in fresh- 

 water forms. 



Altogether 108 species, out of the 139 known to occur in the 

 British Isles, have been recorded, and one or two more may yet be looked 

 for. 



In this list Hygromia revelata is not included ; the record of examples 

 said to have been found at Stanton-on-the- Wolds by Mr. E. J. Lowe 

 being obviously due to some error of observation. Pomatias elegans is also 

 omitted as not indigenous now, though a single subfossil example was 

 found at Scarthing Moor in a superficial deposit. Limncea glabra has been 

 inserted, though there is some doubt as to its actual occurrence at the 

 present day, only a single specimen having been met with. Some forms, 

 which have only been found in the rejectamenta of streams, are added 

 because they are all small species not easily found and probably occur 

 living in the area. 



One of these last, Acantbinula lamellata^ is an interesting species that 

 once spread as far south as the Channel, it having been found in a pleisto- 

 cene deposit at West Wittering on the coast of Hampshire, but to-day it 

 does not occur further south than Reading, in the neighbourhood of 

 which a single example was found a short time ago. The occurrence 

 of this pretty little species imparts a slightly northern quality to the 

 otherwise typically British assemblage. 



An introduction of note is Stenogyra goodalli^ a West Indian form 

 that occurs in hot-houses where it has been introduced in the soil with 

 plants. It was first observed in this country and described from hot- 

 houses at Bristol by Miller ; it has since been found at Kew Gardens 

 and in nurseries in other parts of the country. Mr. Pearson obtained it 

 at Chilwell near Nottingham feeding on the roots of the bulbs of 

 Eucbaris. 



Two other introductions were obtained in 1883 from Mr. Thacker's 

 orchid house on Blue Bell Hill, Nottingham, where they occurred 

 plentifully in moss around orchids. 



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