= 40.= 
Limax maximus Linnaeus 
Plate Ill, Hi 
This species is similar to L, marginatus and L, flavus, but is usually 
larger, yellowish-gray, and spotted with black. Its mucus is colorless. 
Adults are often more than 100 mm. long. 
Distribution: Europe, Asia Minor, Algeria. Introduced into North and 
South America, South Africa, Australia, Hawaii, and many places in the 
United States. 
This slug is common in urban and suburban gardens, cellars, and other 
like places. 
III FRESH-WATER SNAILS 
Subclass PROSOBRANCHIATA 
Order MESOGASTROPODA 
Family BITHY NIIDAE 
An aquatic group of medium to small operculate snails with a worldwide 
distribution. Its species have conical or subspherical shells and a corneous 
or calcareous operculum. This family is of great medical importance be- 
cause some of its members carry the human blood and liver flukes in the 
Orient. 
Parafossarulus manchouricus (Bourguignat) 
Plate IV, G 
Shell broadly conic, imperforate, yellowish-brown to green, usually with 
5-10 spiral ribs or lirae. Operculum thick and calcareous; concentric, 
with a small subcentral spiral nucleus. Adults (with 4-5 whorls) measure 
8-12 mm. in height. 
Distribution: China, Formosa, Japan. 
This species is one of the main carriers of the human liver fluke in the 
Orient. 
Pomatiopsis hupensis (Gredler) 
Plate IV. 
Shell small and slender, conic, imperforate, gray-brown to yellowish, 
usually with many high transverse ribs. Operculum thin, translucent, 
