. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 1232 TUNICATA. large anus. The faecal matter contained in it is greenish and vermiform. The liver (testicle, Krohn) in this species appears to be composed of large, parallel, longitudinal filaments, and terminates posteriorly in a delicate, tapering point. It differs also from the liver of other species in being of a whitish colour. The intestine of the Salpians is usually twisted once or twice either around or within the liver, with the anus terminating nearly free of the latter, near the anterior attachment of the bran
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 1232 TUNICATA. large anus. The faecal matter contained in it is greenish and vermiform. The liver (testicle, Krohn) in this species appears to be composed of large, parallel, longitudinal filaments, and terminates posteriorly in a delicate, tapering point. It differs also from the liver of other species in being of a whitish colour. The intestine of the Salpians is usually twisted once or twice either around or within the liver, with the anus terminating nearly free of the latter, near the anterior attachment of the branchia. The anus is generally on the left side, opening posteriorly. The rectum never traverses the heart. In S. gibbosa and S. infundibuliformis the intestine makes a little more than one turn, the two ends crossing one another a little. It has two coeca, one on each side, which are turned into the centre of the loop of the intestine. Eschricht describes the liver of S. zonaria as conspicuous, enve- loping nearly all the alimentary canal, and consisting of a mass of ccecal tubes, each of which bear, near their free extremities and on one side only, a group of 2—6 minute, short ccecal appendages. The heart is with difficulty observed in dead specimens, but, from its pulsating move- ments, is generally conspicuous in the living animals ; and in these only can the circulatory apparatus be traced out. It is situated in the antero-inferior region of the body, near the visceral nucleus, the anterior attachment of the branchia, and the generative organs. It is a somewhat long, pellucid, tubuliform ve- sicle, enclosed in an immoveable pericardium. A longitudinal vessel or sinus (aorta, of Van Hasselt) traverses the inferior surface of the branchial cavity, and is continued into the in- ferior lip of the posterior orifice, and into the base of the posterior prolongation (if present) of the test. Hence it is retroflexed and recur- rent. It gives off numerous branches at right angles on
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