356 



PAI,UDESTRIN1D/E — CYRENID.*:. 



Bithynia Leach, 1818. 



tentaculata {Linne). 134 



leachii {Sheppard). 135 



VIVIPARID^. 

 Vivipara Montfort, 18 10 {em.). 

 vivipara {Linne). 136 



Jdiluviana {Kunth) [ = clactonensis 

 {S. V. Wood)]. 137 

 contecta {Millet). 138 



VALVATIDiE. 

 V^XvdXdi Milller, 1774. 



piscinalis {Miiller). 139 



V. antiqua Sowerhy. 



cristata Miiller. 140 



ASSEMANIID^. 

 Assemania Leach in Fleming 



(1828), em. 

 gray an a Leach. 141 



POMATIIDiE. 



Pomatias Siuder, 1789. 

 elegans {Miiller). 



ACICULID^. 

 h.Z\ZV\z. LLaitman7i, 1821. 

 lineata {Draparnaud). 

 NERITID^. 



Neritina Zt?///rtn-^, 1809. 

 Theodoxia ALotitfort, 18 10 

 fluviatilis {Linne). 

 Jgrateloupiana Ferussac. 



PELECYPODA. 



EULAMELLIBRANCHIA. 

 ^ UBM YTLLA CEA. 

 DREISSENSIID^ Gray. 

 Dreissensia Van Beneden 



1835 em 

 polymorpha {Pallas). 146 



142 



143 



144 

 145 



147 

 ia8 



UNIONID^. 

 U nio J^efzius, 1788. 

 pictorum {Linne). 

 tumidus {Retzius). 

 jlittoralis La^narck. 149 



Margaritana Schumacher, 18 17. 

 margaritifer {Linnk). i 50 



hwoAorxtdi. Lamarck, 1799. 



cygn^ea {Linne). 151 



CYRENID^. 

 Corh\c\x\3i Megerle, 181 1. 



Ifluminalis {Miiller). 

 Sphaerium Scopoli, 1777. 

 rivicola {Leach). 

 corneum {Linne). 

 lacustre {Miiller). 

 pallidum Gray. 



[provisional]. 



Pisidium Pfeiffer, 1821. 

 amnicum {Miiller). 

 Isupinum A. Schmidt. 

 |astartoides Sandberger. 

 henslowianum {Sheppard) 

 subtruncatum Malm [ = foniinale 

 Jeffreys]. l6i 

 pulchellum Jenyns. 1 6 2 



pusillum {Gmeli/i) [ = fontinale 

 Draparnaud of continental authors]. 



163 

 V. cinerea. • 

 mS^d.Vim. Jenyns. 164 



obtusale Pfeiffer. 165 



gassiesianum Dupuy [ = roseum 



Jeffreys non Schpltz=vcXmm Auctt. 

 non Held^ i66 



153 

 154 



156 



160 



EXPLANATORY NOTES. 



Limax cinereo-niger. — Sufficient first-hand evidence has not yet been 

 adduced to convince me of the specific distinctness of this form. 

 Roebuck says L. hedleyi is a synonym ; Collinge disputes this. 



Limax marginatus Miill. — Those who claim Miiller's name for the 

 L. arborum Bouch.-Chant. on the ground that he states it is found on 

 beech trees, entirely overlook his explicit statement that his species 

 has "Carina dorsi alba, utrinque cinereo-subeffirulescens."^ Relying 

 on this latter feature, Draparnau d, Jeffreys, and others have recog- 



I " Hist. Verm.," ii., lo. 



