298 REFERENCE TO PLATES. 



FIGURES. PAGE. 



2. Branchiae of Octopus. Cuvier, Mem. Moll. Ceph., t. 2 35 



m b r. Branchial muscle, v b r. Branchial vein, n b r. Ar- 

 terial nerve, v c. Vena cava. c b r. Branchial heart, a b r. 

 Branchial artery. 



3. Heart of Octopus vulgaris. Cut open. Cuvier, 1. c 35 



a. Aorta, b. Auricle, c. Valve, d. Net-work of muscle. 



4. Section of eye of Sepia officinalis. Hensen, Zeit. Wiss. Zool., 



xv, t. 12 33 



k. Cephalic cartilage. k'. Eyelid cartilage. w k. White 

 bodies, c. Cornea. L. Lens. A i. Argentea interna. A e. Ar- 

 gentea externa. k Eye cartilage with the thick {equatorial 

 cartilage. i k Iris cartilage, g. Optic ganglion. R e. Retina 

 externa. R i. Retina interna. t p. Pigment, h y. Hyaloidea. 

 c. Ciliary bodies. 



5. Eye and olfactory organ of Sepia. Zernoff, Bull. Soc. Moscow, 



vol. 42, pt. 1, t. 1 33, 35 



a. Olfactory organ, n. Olfactory nerve, b. Eyeball, c. Op- 

 tic ganglion, d ef. Principal ganglia of the brain, g. Ante- 

 rior nerve of siphon, h. Nerves of the mantle ganglion. 

 k. Sympathetic nerve. I. Nerves leading to the cephalic gan- 

 glion and arms. m. Nerve of the eye. n. Olfactory nerve. 

 o. Eye cavity, p. Skin. 



Plate 10. 



Digestive organs, etc., of Nautilus Pompilius. From Owen, 1. c. 



t. 4 29 



a. The hood, or upper part of the oral sheath longitudinally 

 divided, b. Posterior lobes or angles of the hood. c. Poste- 

 rior concavity of the hood. d. The ridge in the same. e. The 

 cut-surface of the above parts. /. Internal surface of the oral 

 sheath, g. External labial processes, h. External labial ten- 

 tacles i. Internal labial processes, k. Internal labial tenta- 

 cles. L Olfactory laminaB. m. The circular fringed lip, 

 longitudinally divided, n. Superior mandible, o. Inferior 

 mandible, p. Muscular attachment of mandibles, q. The 

 superior pair of muscles which retract the jaws. r. The semi- 

 circular muscle which protrudes the jaws, divided longitudi- 

 nally, a. The oesophagus, t. The crop. u. The narrow canal 

 leading to v. The gizzard, w. The intestine, w'. The termi- 

 nal fold of intestine drawn out of its situation, x. The anus. 

 y. The laminated pancreatic bag. z. The liver. 15. A branch 

 of the anterior aorta, which ramifies in the membrane connect- 

 ing the two portions of the terminal fold of the intestine. 

 19. Continuation of the posterior aorta along the dorsal aspect 

 of the crop. 20. Its bifurcation at the oesophagus, to form a 

 vascular circle corresponding to the nervous circle round that 

 tube. 21, 22. Arteries of the crop, gizzard, etc. 



Plate 11. 



1. Venous system of Sepia officinalis. Chiaje, Mem. Anim. Invert., 



t. 89 ' 35 



t> c. Vena cava. r. Renal organs, c v. Venous hearts. 



2. Arterial system of Sepia officinalis. Chiaje, 1. c., t. 90 35 



c. Heart c*. Auricle, b r. Branchiae, a o. Great aorta. 



