270 DESCRIPTION OF PLATES. 



The occasional pathological distension in liver diseases of the veins of the 

 anterior abdominal parietes in the human subject shows that an arrangement may 

 exist in a rudimentary condition in the higher Vertebrata similar to that shown here 

 to exist functionally between the epigastric and the parietal veins ; and the con- 

 nection with a vesico-hemorrhoidal vein, whilst it may be held to foreshadow the 

 arrangement of the umbilical vein in the foetus of Mammals, puts prominently 

 forward the fact that anastomoses exist between the portal and systemic veins. 

 For the 'renal portal' of the Frog, see Jourdain, A. Sc. N. (4), xii., 1859, p. 180. 



f. Point where the transverse branch of the femoral vein of either side 



fuses with its fellow to form the trunk of the epigastric. 



g. ' Renal portal/ or renal inferent vein of the right side, being the other 



branch of the bifurcating femoral vein, which is thus seen to be con- 

 tinuous with the portal systems of both liver and kidney. Conse- 

 quently there are two channels open for the return of the blood to the 

 heart. 



h. Bifid allantoid bladder distended, with ramifications of the vesico- 

 hemorrhoidal veins. 



i. The rectum, which is cut short. 



j. A vesicular, and in this species glandular, dilatation developed upon the 

 Wolffian duct, by which both testicular and renal products pass down 

 to the cloaca. A vein passes directly into the kidney from it. 



k. Vena cava inferior, constituted mainly by the efferent kidney veins, 

 but receiving also those of the testes and fat bodies. 



/. Testis of left side. It has, together with its fellow and with the kidneys, 

 been displaced a little to the right side. 



m. Fat bodies. 



n. Spleen. To the left and a little above the spleen are seen the cut ends 

 of two vessels, one of which receives a factor from that organ, coming 

 itself from the intestine, and the other of which takes origin from the 

 stomach. Both veins join a branch of the epigastric, and are distri- 

 buted to the liver, a small portion of which is seen left immediately 

 above them. 



o. Gall bladder left attached to the epigastric vein by a vein which passes 

 from it to that vessel. 



/. Lung of left side. The cavity seen on the outer side of either lung has 

 its outer wall constituted by the internal abdominal muscle (homo- 

 logous with the internal oblique and transversalis), which arches in- 

 wards in a dome shape, and is connected with the oesophagus and 

 pericardium, the coracoid and hyposternum. In the natural condition 

 of the parts these cavities are however mainly occupied by the lobes 

 of the liver, which nearly entirely cover the lungs in an anterior view. 



q. Heart. The conus arteriosus takes origin from the base of the ventricle, 

 a constriction known as the fretiim Halleri marking the line of sepa- 



