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HELIX. 



The eggs of the Helices are generally round, white, and moderately large 5 

 they are at first rather glutinous, and especially in those species which de- 

 posit them in series or in the form of a chaplet. They are frequently 

 deposited one by one, or in an irregular mass, in holes hollowed in soft 

 ground by the animal ; but generally in natural excavations, cracks in the 

 ground, trees, rocks, or old walls, where there is a constant humidity. At 

 the end of a period, which varies according to the species, and perhaps 

 according to circumstances, the eggs hatch, and a small snail comes out, 

 clothed with a shell (PI. 7, fig. 3) so extremely thin and so nearly mem- 

 branous, that, fearful of the effect of the air and sun, they only quit the 

 holes wherein ihey were born, during the night. They at first grow very 

 rapidly, and afterwards so gradually that the growth may be judged of by 

 the striae of the shell : they probably live very long, but this is a part of their 

 history not very well known. The increase of their bodies necessarily re- 

 quires a proportionate increase of the shell, and at the period when this 

 takes place, the Helices assemble in numbers : the animal remains in a state 

 of repose, buries itself in some cavity, and there produces from every part 

 of its mantle, and especially from the edge (thickened into a pad), a layer of 

 a glutinous, calcareous matter, which lies within the preceding, projecting 

 a little beyond its edge ; it is this point of junction with the new_ layer 

 which forms the stria marking its growth, and it is as much wider as the 

 animal is better nourished and more vigorous. When the shell has attained 

 its full growth, it merely thickens, and in the greater number of species 

 forms a callous pad, more or less thick; it also deposes, on the part of the 

 spire which invades the mouth of the shell, a thin calcareous matter, which 

 joins the two lips, and is called a callosity. (PI. 7, fig. 3.) Although this 

 is termed the complete or finished shell, the animal becomes adult, or has 

 the power of reproduction, long before : but it is important to remark, that 

 the shell of the same individual differs considerably according to the age of 

 the animal. The spire is less elevated as the animal is younger, and the 

 last whorl is consequently much greater in proportion; the umbilicus i s 

 more exposed, the mouth wider, the lip sharper, and the shell thinner. 

 When it is completed, the last whorl swerves from the spiral line which 

 renders the mouth narrower. We also find anomalies which we cannot 

 account for. (V. PI. 7, fig. 12, 13, 14. PI. 6, fig. 13.) 



It appears that the larger species serve as food in several countries. Ac- 

 cording to Pliny, the Romans consumed a great many, and sought them for 

 their tables, and he gives the name of the person who first thought of raising 

 them in a sor t f p ar k an( j fattening them with choice food. L. 8, c. 39. 

 Some authors assert that they are still eaten in different countries, and amongst 

 others in Si'esia, Brabant, Liege, Switzerland, Italy, and several provinces 

 in France. I n the neighbourhood of Rochelle they are said to be parked by 

 putting them one above another in layers, moss or other plants being strewed 

 between each. It is admitted that those which live in elevated spots are the 

 best, and that they partake a little of the taste of the plants on which they 

 teed. The Ashantees eat snails after they have been smoke-dried, and the 

 Tamoul people eat the animal of the Ampullaria (PI. 9, fig. 1), which 

 they c a ll Nette. A great many are sold in the markets of Paris and other 

 great cities, not as food, but to make mucilaginous broths for those who 

 f re attacked with certain disorders of the lungs. One would be still more 

 inclined to doubt the efficacy of snails in curing hernia in its earliest stage, 

 hy producing the contraction of the inguinal ring; yel Bi. Georges Ta*- 



