PLATE VII. 



Fig. 91. — Median sagittal section through a larva of the 6 p. c. stage. 



x 210. pit. pit in the mid-gut. rec. recess between the epistome 



and the mouth. 

 Fig. 92. — Transverse section through a larva of the 6 p. c. stage, x 210. 

 Figs. 93, 94. — Two sagittal (not consecutive) sections through a well fed 



larva of the 8 p. c. stage ; Fig. 93 passes very near the median 



plane, x 210. pit. pit in the mid-gut. 

 Fig. 95. — Transverse section through a larva of the 8 p. c. stage. x 210. 

 Fig. 96. — Posterior right hand corner of the shell of a larva of the 8 p. c. 



stage (ventral view). x 490. 

 Fig. 97. — Posterior portion of the shell from a sagittal section through a 



a larva of the S p. c. stage. x 490. r. horizontal ridge on the 



dorsal shell. 

 Fig. 98. — Dorsal posterior mantle-lobe from a sagittal section through a 



larva of the S p. c. stage. x 490. 

 Fig. 99. — Ventral ganglion and ventral mesentery of a larva, in which the 



Sth pair of cirri have just budded out (from life). In this the jagged 



posterior face of the ventral ganglion, formed by the detachment oi 



blood corpuscles, is seen. x 370. 

 Fig. 100. — Portion of a transverse section through the oesophagus of a 



larva of the 6 p. c. stage, x 912 (immers). 

 Fig. 101. — Left half of the posterior dorsal lobe of liver from a transverse 



section through a larva of the 8 p. c. stage. x 490. al. unicellular 



al";o taken into the liver cells as food. 



ö 



Fig. 102. — Oil globules in the liver from a living larva, x 31.0. 



Fig. 103. — Transverse section through the posterior part of the alimentary 



canal of a larva of the G p. c. stage, x 500. 

 Fig. 104. — Portion of a transverse section through a larva of the 8 p. c 



stage, x 490. o Epithelial thickening at the place where the anus 



is to be opened. 

 Fig. 105. — Portion of a sagittal section (very near the median plane) 



through a larva of the 8 p. c. stage x 500 



