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PROFESSOR T. J. PARKER OK THE 
D. System of the Coronary Veins. 
7. The Coronary Veins. 
There are two coronary veins in Mustelus (Plate 34, fig. 4, Cor. V.), a right 
and a left, situated one on either side of the furrow between the auricle and the 
ventricle. Each receives the veins from its own side of the ventricle and conus 
arteriosus, and, passing backwards, opens into the sinus venosus (fig. 9, Cor. V'.) 
in the immediate neighbourhood of the sinu-auricular aperture (Sin. aur. ap.). 
E. System of the Cutaneous Veins. 
The cutaneous, like the lateral veins, were first described by Robin* as lymphatics. 
He, however, seems to have missed the dorsal and the posterior ventral cutaneous 
veins, and his researches, judging from the abstract of them given by Milne Edwards, 
are imperfect in many particulars. As far as my experience goes the vessels in 
question invariably contain blood. 
8. The Dorsal Cutaneous Vein. 
This (Plate 36, figs. 14 and 15 ; Plate 37, figs. 22 and 24, Dors. cut. V.) is a 
median longitudinal vessel, imbedded in the dermis, and extending from the tail 
to some distance in front of the first dorsal fin. 
Tracing it forwards from the tail, it is found to divide, immediately caudad of 
the second dorsal fin, into two vessels, which embrace the base of the fin, uniting 
again in front of it so as to form a complete loop (fig. 14, d, f 2). On reaching 
the posterior border of the first dorsal fin (fig. 15) the dorsal cutaneous vein 
divides into three branches, one median and two paired; the latter (d, f l) 
extend forwards, one on each side of the base of the fin, and unite in front of it 
in an azygos subcutaneous trunk ; the median branch leaves the skin, and passes 
downwards and forwards in the median fibrous septum dividing the muscles of 
the right and left sides (fig. 22) ; on reaching the vertebral column it turns to 
the left of the latter—in the single specimen in which it was traced out—and, 
continuing its downward course, opens into the left renal portal vein. 
9. The Anterior Ventral Cutaneous Vein. 
Tronc lymphatique median abdominal, Robin, quoted by Milne Edwaeds 
(15). 
This vessel (Plate 36, fig. 14; Plate 37, figs. 21, 22, and 24, Ant. vent. cut. T .) 
lies in the middle ventral line of the abdomen, extending from the shoulder 
* Robin, ‘Revue Zoologique,’ 1845. —Quoted by Milne Edwaeds (15). 
