336 THE BLOOD. 



tity of dry residue and haemoglobin in blood from the carotid artery and 

 from the jugular vein (in cats) is the same. ROHMANN and MUHSAM 

 could not detect any difference in the quantity of fat in arterial and venous 

 blood. The serum from dog's blood has, according to WIENER/ a rela- 

 tively higher globulin content relative to the albumin in the venous blood 

 as compared with the arterial blood. 



Blood from the Portal Vein and the Hepatic Vein. In consequence of 

 the small quantities of bile and lymph formed relatively to the large 

 quantity of blood circulating through the liver in a given time, we can 

 hardly expect to detect by chemical analysis a positive difference in the 

 composition between the blood of the portal and hepatic veins. The 

 statements in regard to such a difference are in fact contradictory. For 

 example, DROSDOFF found more haemoglobin in the hepatic than in 

 the portal vein, while OTTO found less. KriioER finds that the quantities 

 of haemoglobin, as well as of the solids, in the blood from the vessels 

 passing to and from the liver are different, but a constant relation can- 

 not be determined. The hepatic vein, according to Do YON and collab- 

 orators, 2 is richer in fibrinogen than the blood from the portal vein. 

 The disputed question as to the varying quantities of sugar in the por- 

 tal and hepatic veins will be discussed in a following chapter (see Chap- 

 ter VII, on the formation of sugar in the liver). After a meal rich in 

 carbohydrates, the blood of the portal vein not only becomes richer 

 in glucose, but may also contain dextrin and other carbohydrates (v. 

 MERINO, OiTO 3 ). The amount of urea in the blood from the hepatic 

 vein is greater than in other blood (GREHANT and QUINQUAUD). In 

 portal blood FOLIN and DENIS found about the same amount of urea 

 as in the carotid blood. Like HORODJNSKI, SALASKIN and ZALESKi, 4 

 they found that the portal blood was richer in ammonia than the carotid 

 blood. The largest amount of ammonia was always found in the blood 

 from the mesentery vessels of the large intestine. 



Blood of the Splenic Vein is decidedly richer in leucocytes than the 

 blood from the splenic artery. The red blood-corpuscles of the blood 

 from the splenic vein are smaller than the ordinary, are less flattened, and 

 show a greater resistance to water. The blood from the splenic vein is 

 also claimed to be richer in water, fibrin, and protein than the ordinary 

 venous blood. According to v. MIDDENDORFF, it is richer in haemoglobin 



1 Rohmann and Miihsam, Pfliiger's Arch., 46; Wiener, Zeitschr. f. physiol. Chem., 

 82. 



2 See footnote 2, page 253. 



3 Drosdoff, Zeitschr. f. physiol. Chem., 1; Otto, Maly's Jahresber, 17; v. Mering, 

 Arch. f. (Anat. u.) Physiol., 1877, 214. 



4 Grehant et Quinquaud, 1. c. footnote 3, page 333; Folin and Denis, Journ. of biol. 

 Chem., 11 and 12; Horodjnski, Salaskin and Zaleski, Zeitschr. f. physiol. Chem., 35. 



