OF NORTHUMREBLAND AND DURHAM. 



33 



Fam. Helicid^, Jeffreys. 



24. VITRINA, Draparnaud. 



1. "V. PELLUCIDA, Mull. 



Vitrina pelhicida, Gray Turt. Man. 120, t. 3, f. 21. 

 Among decayed leaves and under stones in woods, on old walls, 

 and on the sea banks ; frequent. Abundant in short grass, on 

 and near St. Mary's Island, Hartley ; where, in some states of 

 the weather, it is difficult to walk without crushing numbers of 

 them. 



25. SUCCINEA, Draparnaud. 



1. S. PiTTRis, Linn. 



Succinea amphibia, Drap. Hist. Moll. 58, t. 3, f. 22, 23. 

 Succinea putris, Gray Turt. Man. 178, t. 6, £ 73. 

 Var. Succinea gracilis, Aid. in Newc. N. H. Trans, ii. 338. 

 Succinea Pfeifferi, Gray Turt. Man. 179, t. 6, f. 74*. 

 On aquatic plants in marshy places, and at the borders of ri- 

 vulets, common. 



This species is subject to very great variety. Further obser- 

 vation inclines us to unite with it the S. gracilis of our former 

 Catalogue, though opinions are still very much divided upon that 

 point. The S. Pfeifferi of Rossmassler does not appear to be ex- 

 actly equivalent to our S. gracilis, though doubtless a nearly 

 allied variety, Rossmassler describes it to be thick, and with a 

 pearly lustre inside, which is not the case with ours. There is a 

 very stunted and dwarf variety with the animal nearly black, 

 not uncommon on plants and stones close to the edge of rivulets, 

 and frequently on stones surrounded by the stream ; which, if 

 S. gracilis be retained as a species, seems entitled to a similar 

 rank. 



26. HELIX, Linnceus. 

 1. H. ASPERSA, Miill. 



Helix aspersa, Gray Turt. Man. 128, t. 4, f. 35. 

 In gardens and on hedge sides, common. Very abundant on 

 the sea banks on a limestone soil. 



