ON THE DEVELOPMENT OF LINGULA ANATINA. 51 



can be seen passing from without into the stomach. In section 

 we can see a well stained layer of the basal pieces of the cilia. 



anter. dor. lobe of 

 liver 



gastroparietal band 

 otocyst 



post, dorsal lobe 



of liver 



mid-gut 



funnel of 

 nepbridium 



occ. pst. 

 peduncle 



dorsal mesentery 



Ventral 

 valve 



epistome 

 mouth 



cirrus! 



oesophagus 

 ventral ganglion 



ventral mesentery 



ventral lobe of liver 



intestine 



tube part of 

 nephridium 



ileo-parietal 

 band 



Diagram of a larva of the 10 p.c. stage:— Right side view, the shells, 



the mantle, the body walls, and tbe anterior part of 



the body being sagittall / out off. 



