any one terrestrial mollusk of the subclass Pulmonata of the order Stylommatophora that lacks an external shell but has rudiments of a shell in the form of a calcareous plate or grains inside the mantle. The body is wormlike or cylindrical. There are approximately 100 species in the USSR, most of which belong to the families Arionidae and Limacidae. During the day, slugs hide in damp and shaded places, for example, under stones and forest litter or in hollows or cracks in soil. The animals are active at twilight and during the night when the temperature is 8°–20°C and there is adequate moisture.
Many slugs are injurious to vegetables, tobacco, and other crops. The most dangerous pests are Agriolimax reticulatus, which occurs in the western and northwestern regions of the USSR, and slugs of the genus Parmacella (for example, P. ibera), which are found in the subtropics (Caucasus and Middle Asia). Control measures include draining farmland and pastures, destroying weeds, removing crop residue from gardens and orchards, applying limacides, and surrounding valuable plantings with ditches containing slug repellents (mazut, copper sulfate, ash). Removal of the slugs by hand is also effective. Some slugs serve as intermediate hosts of helminths that infest farm animals.
I. M. LIKHAREV [23–1674–]