THE ANATOMY OF A NEW SPECIES OF BATHYDORIS. 209 



(11) de Lacazk-Duthiers, H., "Histoire anatomique et physiologique du Pleurobranche orange," Ann. 



Sci. Nat. (4), xi., 1859. 



(12) Moquin-Tandon, G., Recherches anatomiques sur VOmbrelle de la Mediterranee, These de Paris, 1870. 



(13) Pelseneer, P., Recherches sur divers Opistobranches, Gand, 1893. 



(14) Thiele, J., "Die antarktischen Schnecken und Muscheln," Deutsche Sudpolar Expedition, 



Berlin, 1912. 



EXPLANATION OF PLATES XVII. AND XVIII. 



Bathydoris broionii. 



Fig. 1. The animal seen from the dorsal side, natural size. 



Fig. 2. General view of the alimentary system from above, b.m., buccal mass ; cr., oesophageal crop ; 

 int., intestine; I., liver; oe., oesophagus; p.m., lateral pads of the inner lips; s.g., salivary glands. 



Fig. 3. Buccal cavity laid open from above. J., jaws ; o., odontophore ; 03., oesophagus ; P. J., pads of 

 the jaw ; p.m., pads of inner lips ; R., radula. 



Fig. 4. Portion of a half-row of the radula. L. 1 -L. T , lateral teeth 1 to 5 ; Rh., rhachidian tooth. 



Fig. 5. Stomach and adjacent parts of the alimentary canal laid open ; the cut is continued into the 

 posterior lobe of the liver, b.o., bands on the wall of the crop ; I., liver ; int., intestine ; l.t., liver ducts; s.r., 

 gastric caecum ; st., stomach. 



Fig. 6. Section across an oesophageal band, b.c, brown cones ; ct., cuticle ; ep., epithelial layer ; m., 

 muscle layers. 



Fig. 7. Nervous system, b.co., buccal commissure ; e.g., cerebral ganglion ; gen.g., genital ganglion ; 

 g.o.n., gastro-cesophageal nerves ; ped.g., pedal ganglion ; ped.com., pedal commissure ; p.ped.com., parapedal 

 commissure ; pl.g., pleural ganglion ; s.g.l., buccal loop ; st.g.g., stomato-gastric or buccal ganglion ; v.l., v.l. 1 , 

 visceral loop ; v.n., visceral nerve. 



Fig. 8. Kidney with thin dorsal wall removed, a.c, aortic bulb ; b.g}, b.g. i[ , lobes of the kidney to which 

 the blood glands are attached; cart., cephalic artery; h.g., hermaphrodite gonad; int., intestine; o.v., 

 opening of aortic swelling iuto the ventricle; r.d., renal tube to exterior ; r.p.d., reno-pericardial duct; r.s., 

 renal syrinx. 



Fig. 9. Arterial system, a.c, aortic bulb; b.g}, h.g. [i , blood glands; cart., cephalic artery; cer.art., 

 cerebral artery; bucart., buccal artery; g.art, genital artery; lab.art., labial arteries; lac, lacuna under 

 buccal mass; ped.art., pedal artery; sal.g., salivary gland; v.art., visceral artery. 



Fig. 10. Diagram of the afferent and efferent vessels, a.b.v., afferent branchial vein; aur., auricle; 

 cs., circular sinus ; e.b.v., efferent branchial vein; h.v., haemoccelic vessels; m.s., median sinus. 



Fig. 11, a and b. Diagram showing the relation of the penis to its sheath in the retracted and protruded 

 condition. 



Fig. 12. General view of the reproductive system. a.L, atrial lips ; a.g., albumen gland; amp., ampulla ; 

 b.c, bursa copulatrix ; c.h.d., common hermaphrodite duct ; f.o., female opening ; h.g., gonad ; m.g., mucus 

 gland; o.d., oviduct; p., pitted pad on penis; p.s., penis sac; v.d., vas deferens; vg., vagina. 



