MOLLUSCA IN THE NEIGHBOURHOOD OF PONTEFRACT. 429 
H. pulchella. The White Snail.—Gwyn Jeffreys says the shell 
of this species is transparent, but Tate describes it as opaque. 
Judging from specimens found here the ridged form should be 
considered the type, and the smooth white form a subspecies or 
variety. On July 14th last I found several specimens of the 
glossy, smooth form amongst water-weeds which had been 
dragged from a canal. I have always found the ridged ones in 
dry situations on the tops of walls. The latter are frequent on 
walls and rocks in the vicinity of Pontefract. I have occasionally 
found the shell of this species covered with minute grains 
of sand. 
Bulimus obscurus. The Dull Twist Shell.—Frequent. Gene- 
rally smooth, not covered with particles of sand, or in any other 
way concealed. 
Pupa umbilicata. The Umbilicated Chrysalis Shell.—Common. 
P. marginata. The Margined Chrysalis Shell.—Abundant. 
Vertigo minutissima. The Least Whorl Shell.—Frequent. 
Clausilia rugosa. The Dark Close Shell.—Plentiful. 
Var. tumidula. If this is sufficiently marked to be a variety, 
the short tumid form of C. laminata should be regarded as a 
variety. I have seen adult specimens of this tumid form of 
laminata with two whorls less than the type, and much more 
ventricose near the mouth. 
Cochlicopa lubrica. The Common Varnished Shell.—Abundant. 
Var. lubricoides.— Common as the type. 
Achatina acicula. The Needle Agate Shell.—Local; gre- 
garious. Numerous in certain places. 
Fam. CARYCHIIDE. 
Carychium minimum. The Little Sedge Shell.— Common in 
woods and plantations. 
All the above-named snails and slugs may be found within 
two miles of Pontefract, and very many of them within the 
boundaries of the town itself. The under-mentioned species 
have been found at Wentbridge, about four miles to the south- 
east :— Helix lapicida, Vertigo antivertigo, V. pygmea, V. substriata, 
V. pusilla, V. edentula, and V. minutissima. All these species 
of Vertigo, may be found within a limited area, where the River 
Went has cut a deep passage through the limestone rocks. 
