. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. CIRRHOPODA. 689 Fig. 341. stomachs, and Burmeister once found part of an annelid of unknown species. The food is carried towards the mouth by currents pro- duced by the rapid motions of the arms, which, in most of the species, are constantly spread out and drawn in, alternately, with great regularity. The mouth is situated just at the bottom of the funnel-shaped cavity formed by the spread arms (b,fg. 340). In the Lepads its position is close to the trans- verse adductor muscle. Its jaws form a round protuberance,
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. CIRRHOPODA. 689 Fig. 341. stomachs, and Burmeister once found part of an annelid of unknown species. The food is carried towards the mouth by currents pro- duced by the rapid motions of the arms, which, in most of the species, are constantly spread out and drawn in, alternately, with great regularity. The mouth is situated just at the bottom of the funnel-shaped cavity formed by the spread arms (b,fg. 340). In the Lepads its position is close to the trans- verse adductor muscle. Its jaws form a round protuberance, which presents itself very con- spicuously immediate- ly on separating the arms. It might al- most be regarded as a head, so prominent is it (Jig. 341, b, b) ; but we find it composed only of the lip and jaws, with their muscles. The lip over-arches the jaws; it is horny, and furnished with minute palpi. There are three pairs of jaws. The first or outer pair are thin horny plates of an oval form, fringed along their opposing sides with long stiff hairs. The other two pairs are curved and deeply serrated on their opposed surfaces. The middle pair bears a small palp on its lateral margin. In some species, a small tongue has been found. All these parts bear a close re- semblance to the same organs in some of the Crustacea. The oesophagus is short; its lining membrane is somewhat horny, stiff enough permanently to distend the whole canal; be- fore entering the stomach, its diameter is con- siderably enlarged. It receives the ducts of two salivary glands. The stomach (c,Jig. 341) is capacious; externally, it presents an irre- gular mamillated surface, studded with nu- merous small prominences closely set, which are the outersurfaces of hepatic cells, formed in a layer of glandular tissue that closely in- vests the walls of the stomach. These cells communicate directly with its general cavity (a, Jig. 342). There is no other organ that can be regarded as a liver.* Two ccecal appen-
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