. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Viscera of Poulp.* may serve as accessory respiratory organs. The valvlilar structure of the orifices is opposed, however, to this view; while it supports the doctrine of their being excretory outlets. The venous follicles may, therefore, serve as emunctories, by means of which the blood is freed of some principle that escapes from their external pores; or they may alter the blood by adding something thereto; or, like the spleen, they may assist in converting arterial to venous blood. As a secondary function they may ser
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Viscera of Poulp.* may serve as accessory respiratory organs. The valvlilar structure of the orifices is opposed, however, to this view; while it supports the doctrine of their being excretory outlets. The venous follicles may, therefore, serve as emunctories, by means of which the blood is freed of some principle that escapes from their external pores; or they may alter the blood by adding something thereto; or, like the spleen, they may assist in converting arterial to venous blood. As a secondary function they may serve as temporary reservoirs of the venous blood whenever it accumulates in the vessels either from a general expansion, or from a partial impediment in its course through the respi- ratory organs; and thus the cells or follicles, which are endowed with a motion of systole and diastole, like the auricles of the heart, may serve to regulate the quantity of blood trans- mitted to the gills. The branchial ventricles (d, d,fg. 225) are appended to the roots of the gills : in the Octo- poda they are simple pyriform muscular cavities (k, k,Jig. 226,) generally of a blackish grey co- lour; in the Decapoda they are elliptical or trans- versely oblong, of a light grey or pale red co- lour, and have a white fleshy appendage (e, e, fig. 225,) hanging to their lower surface or their external side. The connecting pedicle is hollow, and communicates with a small cavity in the substance of the appendix. Internally these ventricles are deeply impressed with cells * From Mayer, Analecten fur Vergk-ichcndc Anatomic, tab. v. 541 and decussating carneae columnoe (k,jig. 226), and where they com- municate with the ve- nous sinus two semi- lunar valves (I) are placed to prevent re- gurgitation . Their func- tion is to accelerate the circulation through the branchiae ; and by this simple addition to the respiratory appa- ratus, the two gills of the Dibranchiata are rendered equal to the office of prep
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