Lectures on the comparative anatomy and physiology of the invertebrate animals : delivered at the Royal College of Surgeons . longitudinal plicae: in boththe Octopus and Argonaut it dilates, 226 soon after having passed throughthe cranium, into a long ingluvies,forming a large cul-de-sac at itscommencement; but in the Deca-pods {fig. 226, a) it continues nar-row and of uniform breadth to thestomach. This cavity (c) is anelongated sac, presenting, in thedispositton of its muscular fibres, inthe proximity of the cardiac (d) andpyloric (e) orifices, and in the thick-ness of the epithelial lining,
Lectures on the comparative anatomy and physiology of the invertebrate animals : delivered at the Royal College of Surgeons . longitudinal plicae: in boththe Octopus and Argonaut it dilates, 226 soon after having passed throughthe cranium, into a long ingluvies,forming a large cul-de-sac at itscommencement; but in the Deca-pods {fig. 226, a) it continues nar-row and of uniform breadth to thestomach. This cavity (c) is anelongated sac, presenting, in thedispositton of its muscular fibres, inthe proximity of the cardiac (d) andpyloric (e) orifices, and in the thick-ness of the epithelial lining, the usualcharacters of the gizzard. The in-testine, at a short distance from Ulthe pylorus (e), communicates witha glandular and laminated sac (g),analogous to that in Nautilus, andpresenting a similar globular formin Rossia and Loligopsis; it iselongated in LoUgo vulgaris, andspirally convoluted in Sepia andLoligo sagittata (f). It receivesthe biliary secretion between twobroad lamella, as in Nautilus. Theintestine is very short in all theDibranchiates. In Octopus it isbent upon itself {fig. 227. r), as in ^^^^ ^^^^^^. CEPHALOPODA. 623 227 Nautilus; but in Sepia and Loligo {fig. 226, i) it is continued for-wards in a straight line, from the stomach to the vent. Its internalmembrane is longitudinally folded, but is smooth at the short tractbeyond the entry of the duct of the ink-bag (Jt) ; its termination isconstricted eitlier by the muscular fibres of the branchial septum, orby those which connect together the pillars of the funnel. In mostDecapods provided with fins for swimming forwards, the anus canbe closed by rhomboidal {Sepia) or triangular fleshy valves {Sepio-teuthis): in LoUgopsis these are modified into the form of antennalfilaments. There is no ciliated epithelium in the intestinal canal ofthe Cephalopods. The liver {fig. 227, x) is of large size in the Dibranchiates, but ofmore simple form than in Nautilus. It is usually of a reddish yellowcolour. In Sepia it is d
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Keywords: ., bookauthorowenrichard18041892, bookcentury1800, bookdecade1850
