58 



Lessons in Zoiiiogy. 



They throw out so much mucus in their efforts to 

 remove the dry particles that 

 they s"oon exhaust their strength 

 and die of weakness. In Eu- 







tiG. 8 FlO. 9. 



rcpe, where they do so much mischief in the vineyards, 

 the people take their revenge by eatmg them in turn. 



p .> i^.onsiilo havH bnt ooe pair of tentacles, at the base of which 

 are the eyes. Some of them, like 

 the one seen in Fig. 6, have a 

 horny scale, or opercnlnm, vhich 

 oloees the aperture of their ahella, 

 and the month on the end of a 

 roatrnm, or beak, and also breathe 

 by gills. Othera (Fig. 7) have no 

 opercnlnm and ' no rostrnm, and 

 are air-breathers. 



A t the aeashore we shnll find the 

 large Lunatia (Fig. 8), Fig. 9 

 shows thia as it crawls abont partly 



bnried in the sand, with its broad foot extended and the shell 



almost covered by the 



soft body. With the 



teeth on its tongne 



(Fig. 10) it drills into 



the shells of other mol- 



Inska and eats ont their 



b o d i e a through the 



hole. Thia anail laya 



its eggs in tha " aand 



collars" (Fig. 11) we have so ofien picked op on the beach, the 



roand spots on them being egg-oasea, and each one containing 



several eggs. 



Fta, in. 



Fig. u. 



