46 NILS HJ. ODHNER 



Explanation of Figures. 



Fig. 1. Part of the radula of Tritonia griegi n. sp. X 1^- 



Fig. 2. GoniaeoUs typica M. Sars. After G. O. Sars 1872. 



Fig. 3. GoniaeoUs lobata Odhner (= G. typica). After Odhner 1907. 



Fig. 4. Goniœolis lobata, pharyngeal bulbus in sagittal section, labial disc 

 retracted. X 8. 



Fig. 5. Labial disc of Goniœolis lobata, with the jaws in the centre. X 15. 



Fig. 6. Anatomy of GoniaeoUs typica. a anus; g glans penis; h herma- 

 phrodite gland; the broken line shows its extension; i intestine; 

 I liver, cut away on the right side, the dark line showing its ex- 

 tension; I. C- liver canals from the right anterior lobe; n nephri- 

 dium; oe oesophagus; p pericard, with heart, showing two veins 

 dedouching into the auricle and the aorta emerging from the ven- 

 tricle ; the broken line beneath the pericard marks the extension 

 of the posterior liver lobe; ph pharynx; p. t. pericardial tube of the 

 nephridium; s stomach, the dorsal and ventral walls of which are 

 cut away to show the pharynx; u nephroproct. 



Fig. 7. Nervous system of GoniaeoUs typica. b buccal ganglia; c cerebral 

 centra; 1 rhinophorial nerves; 2 nerves of the integument of the 

 head; 3 vestigial optic nerve?; 4 labial nerve; 5 circumbuccal nerve ; 

 6 anterior lateral nerves (to velum and sides of the head); 6i latero- 

 palliai nerve (to the genital organs and the musculature in front 

 of the penis); 7 anterior pedal nerves (to the anterior part of the 

 foot); 8 nerve to the radular sac; 9 posterior pedal nerves (to the 

 median and posterior part of the foot); 10 pallio-dorsal nerve (to 

 the sides of the body). 



Fig. 8. Genital organs of GoniaeoUs typica. a ampulla of the herma- 

 phrodite duct; al albuminiparous gland; p penis; r. s. receptaculum 

 seminis; its upper wall cut away to show the entrance into the 

 mucous gland (above it) as well as the fold in the vagina); v. d. vas 

 deferens. 



