A HISTORY OF HERTFORDSHIRE 



Helicella virgata (Da C.) 



itala (Linn.) 



caperata (Mont.) 



cantiana (Mont.) 



Hygromia fusca (Mont.). Gallows Hill, 

 Haileybury 



granulata (Aid.) 



hispida (Linn.) 



rufescens (Penn.) 



Acantbinula aculeata (Moll.). Hitchin ; Swiss 

 Cottage, Cassiobury Park ; Hoddesdon 

 Fields 



Vallonia pulchella (Mull.) 



Helicigona lapicida (Linn.). Hitchin ; Tring ; 

 Sandridge ; Gallows Hill, Haileybury 



arbustorum (Linn.) 

 Helix aspersa, Mtill. 



pomatia, Linn. Hitchin ; St. Albans ; 



Harpenden ; Marford Bridge and 

 Waterend, Wheathampstead ; Gallows 

 Hill, Haileybury 



nemoralis, Linn. 



kortensit, Milll. 



Buliminus montanus (Drap.). Hitchin 



abscurus (Mull.) 

 Cochlicopa lubrica (Mtill.) 



Azeca tridens (Pult.). Hitchin ; Sandridge 

 Ctecilianella acicula (Mull.) 

 Pupa secale, Drap. Beech woods at Aldbury, 

 Tring 



cylindracea (Da C.) 



mtucorum (Linn.) 



Sphyradium edentulum (Drap.). Swiss Cottage 



Woods, Cassiobury Park 

 Vertigo antivertigo (Drap.). Hitchin 



pygmeea (Drap.). Hitchin ; Ware ; Rye 



House 



moulinsiana (Dup.). Near Hitchin ; near 



Broxbourne 



Balea perversa (Linn.). Hitchin 

 Clausilia laminata (Mont.) 



bidentata (Strom.) 



biplicata (Mont.) 



rolphii, Gray. Gallows Hill, Hailey- 



bury 



Succinea putris (Linn.). In addition to the 

 type a variety, which has been described 

 as a separate species, under the name of 

 S. virescens, has been found at St. Albans. 

 e/egans, Risso. Hemel Hempstead ; Gor- 

 hambury, St. Albans ; Ware 



b. BASOMMATOPHORA 



Carychium minimum, Mtill. Hitchin ; Swiss 

 Cottage, Cassiobury Park ; Haileybury 



Anychii jfaviatiia, Mull. 



Velletia lacustris (Linn.). Sopwell, St. Albans ; 

 Hoddesdon Fields 



Limntsa auricularia (Linn.) 



pereger (Mtill.) 



palustris (Mull.) 



truncatula (Mull.) 



stagnalis (Linn.) 

 Planorbis corneus (Linn.) 



a/bus, Mull. 



g/aber, JefF. St. Margaret's 



nautileus (Linn.) 



carinatus, Mull. 



marginatus, Drap. 



vortex (Linn.) 



spirorbis, Mull. 



contortus (Linn.) 



fontanus (Lightf.) 



lineatus (Walker). Ware 

 Physa fontinalis (Linn.) 



hypnorum (Linn.). Hitchin 



II. PROSOBRANCHIATA 



Bythinia tentaculata (Linn.) 



leachii (Shepp.). Hitchin ; Ware 

 V'mipara vivipara (Linn.) 



Vafoata piscina/is (Mull.) 



cristata, Mull. Hitchin ; Ware 

 Pomatias elegans (Mtill.). Hitchin ; Ashridge 



Park, Tring ; Gorhambury Park, St. 

 Albans ; near Wheathampstead ; 

 Brocket Park, Welwyn ; Gallows Hill, 

 Haileybury 

 Neritina JJuviatilis (Linn.). River Lea 



B. PELECYPODA 



Drelssensia polymorpha (Pall.) 

 Unio pictorum (Linn.) 

 Anodonta cygn&a (Linn.) 

 Spheerium rivicola (Leach). Rickmansworth ; 

 River Lea 



corneum (Linn.) 



'lacustre (Mull.). Hitchin ; Rickmans- 



worth ; Ware 



Pisidium amnicum (Mflll.) 



pusillum (Gmel.). Hitchin ; Watford ; 



Ware 



nitidum, Jenyns. Watford ; Ware 



fontinale (Drap.). Sopwell, St. Albans ; 



Rickmansworth ; Ware 



milium (Held.) 



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