20 FIKST BOOK OF ZOOLOGY. 



eggs will hatch out tiny snails, and these will attain half 

 their mature size the first season. 



ooo„o o 

 oo "^ 



Fig. 23. — a, Eggs of Land Snail; &, Young Snail just hatched; c, Toung Snail Bomewhat 

 advanced : b and c are magnified. 



19. If the pupil will also collect a lot of fresh-water air- 

 breathing snails, and keep them alive, they will deposit their 

 eggs upon the sides of the glass jar in which they are con- 

 fined. These eggs will be oval in shape, and transparent, 

 and will be inclosed in a transparent, jelly-like substance. Fig. 

 14, H, represents the appearance of a cluster of these eggs. 



Fig. 21: shows a cluster of eggs with the appearance of 

 two eggs highly magnified, showing the young snails as they 

 appear within the egg. 



a i e 



Fig. 24. — a, Cluster of Eggs of a Fresh-W.ater Snail; 6, d, Eggs enlarged, showing the 

 young Snails within the Eggs. 



With the aid of a magnifying-glass, the eggs may be 

 watched from day to day, and the young snail can be seen in 

 its various stages of growth. 



