816 Dr Grant on the Structure and Characters of 



stomach, makes a long curve downwards behind the Ipft branchial 

 heart, like another coecum, before it mounts upwards on the fore 

 part of the liver, to terminate at the base of the funnel. The liver 

 is short, spherical, of the usual orange-yellow colour, composed of 

 the ramifications of vessels filled with a coloured fluid. In the 0. 

 vulgaris it is cylindrical, from the greater length of the body ; and, 

 for the same reason, it is very long and cylindrical in the L. sagit- 

 tata. Its canals are not surrounded by the pancreatic glands, which 

 I have shewn, in the L. sngittata, to embrace and communicate 

 wjth these ducts during their whole passage from the bver to the 

 spiral stomach, and which were mistaken for the ovarium at a pe- 

 riod when the structure of these animals was very little known, 

 (See Edin. Phil. Journ., vol. xiii. p. 197). The want of these 

 glands in the O. ventricosus is compensated for by the very large 

 inferior pair of salivary glands. The ink-bag is deeply imbed- 

 ded and nearly concealed in the substance of the liver, but it 

 sends out its excretory duct from the lower and fore part of that or- 

 gan, to terminate as usual in the anus. The colour of the ink is quite 

 different from that of the L. sagittata ; and as the colour of this sub- 

 stance is constant in each of the cephalopodous animals, a more in- 

 timate acquaintance with this character might be useful in tracing 

 relations among the different species. The colour of the ink in the L. 

 sagittata is a deep brown, approaching to yellowish-brown, when 

 much diluted, and corresponds remarkably with the coloured spots on 

 the skin of that species. In the 0. ventricosus, the colour of the ink 

 is pure black, and is blackish-grey when diluted on paper. The ink, 

 brought in a solid state from China, has the same pure black colour 

 as in the ventricosus, and differs entirely in its shade, when diluted, 

 from that of the L. sagittata, as may be seen from specimens 

 of these three colours on drawing-paper. Swammerdam suspected 

 the China ink to be made from that of the Sepia, Cuyier found it 

 more like that of the Octopus and Loligo ; but different kinds of that 

 substance are brought from China, probably made from different ge- 

 nera of these animals, where they abound of gigantic size. Ink is at 

 present made from these animals in Italy {Cuv. Mem. p. 4), and from 

 the immense shoals of the L,. sagittata cast ashore every spring in 

 the Firth of Forth, it might likewise be manufactured here. The 

 ink is not contained in a simple cavity attached to the liver, but is 

 diffused through a soft cellular substance which fills the ink-bag, 

 and must render more tedious the preparation pf this substance for 

 the arts. 



The oesophageal ganglia, compared to the brain and cerebellum of 

 vertebral animals, were-^small, white, soft, without internal cavities, 

 lodged in open recesses of the'cartilaginous ring surrounding the oeso- 

 phagus, and were separated from the oesophagus only by a thin tran- 

 sparent membrane, to which they firmly adhered. The large reniform 

 optic ganglia, the band of nerves proceeding from these to the retina, 

 the white pulpy glandular masses within the back part of the sclerotic, 

 the division of the lens, and the general structure of the eye, are 

 the same as in the vulgaris. At the bottom of the large shut sphe- 

 rical cavities of the ears, which were capable of containing a garden 

 pea, |ay a very delicate membranous sac, containing a little fluid, 



