. A text-book of agricultural zoology. Zoology, Economic. SLUGS AND SNAILS. 271 the slime is also yellowish. The shell consists of a number of small separate calcareous grains. This species is a scavenger as well as being injurious. Another curious group of Slugs belong to the genus Testacella. These molluscs (fig. 142), of which there are three species in England, feed almost entirely on earthworms. The TestacellsB are the only true predaceous land mollusca. They hunt the earthworms in their bur rows, and devour huge lobworms much larger than themselves. The mouth is furnished with long curve
. A text-book of agricultural zoology. Zoology, Economic. SLUGS AND SNAILS. 271 the slime is also yellowish. The shell consists of a number of small separate calcareous grains. This species is a scavenger as well as being injurious. Another curious group of Slugs belong to the genus Testacella. These molluscs (fig. 142), of which there are three species in England, feed almost entirely on earthworms. The TestacellsB are the only true predaceous land mollusca. They hunt the earthworms in their bur rows, and devour huge lobworms much larger than themselves. The mouth is furnished with long curved teeth (t), so as to hold the victim. They live for four or five years. The eggs are laid separately, and «^^'»d"ia; w, worm; t, teeth from resemble hen's eggs in shape, and have a very thick skin. Only six or seven ova are laid,. Fig. 142.—Testacella. Testacella hdliotidea: b, head; Snails (Hblioid*). The SnaUs, like Slugs, are nocturnal and crepuscular, seldom crawling about in the daytime, unless after heavy rains. The latter habit has given rise to a popular idea that snails come in rain-clouds. When the breeding season is on, the male organs are supplemented by one or more curious crystalline darts, which they thrust out at one another: these curious structures, found in special sacs called " dart-sacs,'' are peculiar to the genus Hdix. The eggs are laid in batches in slanting galleries underground formed by the " mother'' snail: they are white, round, semi- transparent bodies. The following snails have been brought to the author's notice as being very injurious : The Garden Snail {Helix aspersa), the Wood Snail {H. nemoralis), the Strawberry Snail {H. rufescens),. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Theobald, Frederick Vincent, 1868-1930. Edinburgh and London, W. Blackwo
Size: 1230px × 2031px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1899
