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In the canal which leads to the gizzard, the lining membrane puts on a villous 

 appearance, and is disposed in distinct close-set longitudinal rugae {b. fig. 8. pi. 8.). 



The gizzard, as in the genus Octopus, very much resembles that of the Fowl, 

 being girt by two broad radiate muscles, which are of the thickness of two lines. 

 It is lined with a thick cuticular membrane, delicately furrowed and adapted to 

 numerous fine ridges, which traverse longitudinally the whole interior of the 

 cavity. This membrane, as commonly found in gizzards, was detached from part 

 of the parietes, and adhered very slightly to the remainder {d. tig. 8. pi. 8.). 

 The pyloric orifice is close to the cardiac, and is guarded by a valve, apparently 

 to prevent a too ready egress of matter from the gizzard. 



The contents of this part of the alimentary canal were in smaller fragments 

 than in the crop, but of the same nature : the fragments of shell are comminuted 

 apparently by mutual attrition, as there were no particles of sand or pebbles 

 present adequate to produce this effect. 



The globular cavity (/. fig. 8. pi. 8.), which communicates with the intestine at 

 a little distance from the pylorus, is occupied with broad parallel laminse, which 

 are puckered transversely, so as to increase their surface and cause them to ap- 

 pear more numerous than they really are ; their texture under the lens is seen 

 to be follicular, and evidently fitted for secretion. The bile enters this cavity 

 at the extremity furthest from the intestine, by a duct large enough to admit a 

 common probe. Tlie two laminae on each side of the entrance of the duct increase 

 in breadth as they approach the intestine, and are continued in a curved form 

 along that canal, being gradually lost in its inner membrane ; the lamina next 

 the gizzard (g. fig. 8. pi. 8.) is peculiarly enlarged, so as evidently to present an 

 obstacle to the regurgitation of bile towards the gizzard. A similar structure 

 exists in the intestine of Loligo. 



With respect to the nature of this globular laminated bag, — its reception of 

 the biUary secretion renders it in some measure analogous to a gall-bladder ; but 

 most probably its chief use is to pour into the commencement of the intestinal 

 canal a fluid which is necessary for the completion of digestion, so that, Uke the 

 laminated and spiral caecum of the higher Cephalopods, and the pyloric appen- 

 dages of Fish, it is essentially a simple form of pancreas. 



Tlie interior of the remainder of the alimentary canal in Nautilus presents 

 a few longitudinal rugae and slight transverse puckerings. It was filled with 

 smaller fragments of crustaceous shell similar to those in the gizzard. There 



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