178 TRANSACTIONS LIVERPOOL BIOLOOICAL SOCIETY. 



male stage; c. and d., do. in female stage; 

 ph., pharynx; v.s,, seminal vesicle; g., gut; 

 ov., germ gland. 



Plate VI. 



Fig. 7. Transverse section through region of brain of 

 Graffilla buccinicola ; ep., ciliated epithelium; 

 br., brain; ph., pharynx (posterior end); at., 

 genital atrium ; g.o., genital pore; e., eye. 



Fig. 8. Longitudinal section of specimen with male 

 organs developed, ep., epidermis ; r.m., cir- 

 cular muscles ; l.m., longitudinal muscles ; 

 br., brain; ph., pharynx; oe., oesophagus; 

 ph.s., pharyngeal sack; g.o., genital pore; r.s., 

 rudiment of receptaculum seminis ; p., penis ; 

 v.s., seminal vesicle. 



Fig. 9. Transverse section of G. buccinic.Gla in the 

 female stage, passing through body near the 

 apex of the loop formed by the germ glands. 

 g.c, cavity of gut ; ger. p., proximal limb of 

 germ gland ; ger. d., distal do. ; y., yolk gland. 

 Seminal vesicle with penis retracted. 

 Do. penis protruded, from the same specimen 

 under higher pressure. 



Scheme of relationships of the female apparatus 

 constructed from sections, at., atrium; r.s., 

 receptaculum seminis ; sh. gl., shell glands ; 

 ger., germ glands. 



Fig. 13. Penis, strongly magnified, from a pressure 

 preparation. 



Fig. 



10. 



Fig. 



11. 



Fig. 



12. 



