SCIENCE-GOSSIP. 



i7 



Fig. 6.— The thickening process is being carried 

 on, the shell being considerably heavier and more 

 massive. 



Fig. 7. — The adult shell in which almost the 

 maximum of thickening has been reached, and the 



which loses its top whorl as it grows ; the partition 

 which divided the uninhabited portion of the shell 

 from the rest is shown. 



Fig. 9. — A young shell of the same, still retain- 

 ing its apex, and from its position on the plate 



I 



SOMI. I- kPM ' 



broadening of the shell achieved : the longitudinal 

 expansion of the lip, too, lias now hidden th* 

 of the younger shell 



. 11 are •digraphs ol three landsbells 

 which show the columella and the interim of the 



'•hell as well a* other points noted \»:\ 



■ —A shell of Bulimia d< elUUui from Malta, 



bowing how much shell has been discarded by 

 fig. 6, 



Fig. 10. — Clauiilia twinhoei from Formosa, 

 showing the clausium or clausilium which guards 

 the entrance of the shell. 



Fig 11 Coehlotlyla phiUpplnensit from the 

 Philippine Island 



