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pericardiac cavity, are furnished with clusters of spongy cellular 

 or glandular bodies, which open into the veins by conspicuous 

 foramina ; these have been found in all Cephalopods. Owen 

 {ojp. cit.) thinks that these follicles relieve the vascular system by 

 affording a temporary receptacle for the blood when it accumu- 

 lates in the vessels from expansion or from impediment to the 

 circulation from the varying pressure to which the animal may 

 be subjected at different depths in the ocean, analogous to the 

 rete murahile of Cetacea, or the venous sinuses of fishes ; and 

 that they may also purify or modify the blood, somewhat like the 

 spleen of higher animals. These bodies have been regarded as 

 absorbents, a rudimentary portal system, a spleen, accessory 

 branchiae, blood-reservoirs, &c. ; according to Von Siebold, {op. 

 cit. p. 292,) they can now be positively regarded as kidneys, for 

 by chemical analysis it has been found that they secrete uric acid. 

 They consist of a tissue of contractile fibres, among which are 

 branches of the venae cavce — the urine is secreted from the 

 external surface, escaping into the peritoneal cavities. Accord- 

 ing to Harless, these appendages of the veins must be regarded 

 as everted glandular follicles, the urine-secreting cells being situ- 

 ated externally and the bloodvessels within — a curious histo- 

 logical fact. 



The skin is soft and tender. In the layer analogous to the 

 rete mucosum are immense numbers of chromatic contractile 

 cells, containing a coloring matter ; in the Argonaut, these cells 

 possess the greatest variety of color ; by their contraction and 

 dilatation, and by the action of the surface tissue producing the 

 rapidly changing tints in the skin when exposed to the light. 



The sexes are distinct, though the specimens usually found are 

 all females, the males having been described as parasites until 

 recently. The ovary is single, situated at the bottom of the 

 visceral sac, consisting of a spherical capsule, and ovisacs at- 

 tached to its internal surface, connected in bunches. The ova 

 escape by a single opening into a short single passage, which 

 divides to form the two oviducts, ascending with several convo- 

 lutions to their widely separated orifices at the base of the 

 branchiae ; there are no laminated glands, as in many genera, 

 serving for the production of an external covering to the ova 

 and for connecting them together; their ova are, therefore, con- 



