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THE FORMATION OF FIBRIN. 
The formation of fibrin and its transformation goes on in 
the human body, M. Sequard tells us, not improbably to the 
extent of many pounds per diem. The researches of 
Schmidt and Bidder have shown that, judging from the 
amount of secretions, organic transformations must be verv 
great. The dog, for instance, secretes in twenty-four hours 
a quantity of gastric juice equal in weight to one tenth of the 
animal itself. Again, twenty grammes of bile are produced 
every day in a dog for every kilogramme he weighs. These 
secretions prove that great changes are continuallv going on 
in the blood. Now it seems that true fibrin, such as is 
coagulable spontaneously in the air, disappears from the 
blood which returns from the liver and the kidneys; and if, 
says M. Sequard, it be true that the liver and kidneys are the 
organs in which the fibrin is transformed into other prin¬ 
ciples, we must admit that in man four or five kilogrammes of 
fibrin undergo daily transformation there. Moreover, as the 
quantity of this principle in healthy blood does not vary, it 
follows that in the twenty-four hours four to five kilogrammes 
of fibrin are produced. 
VARIATIONS IN COLOUR OF THE VENOUS BLOOD. 
M. Claude Bernard, in following up his discovery of 
the variations in colour of the venous blood of glandular 
organs, has been led to study the respective influence of the 
cerebro-spinal and sympathetic systems of nerves, and has 
arrived at some very interesting conclusions, which have just 
been published in the Comptes liendusoi the French Academy 
of Science. He has chosen for the subject of experiment 
the sub-maxillary gland of the dog, on account of the inter¬ 
mitting nature of its secretion, which renders the variations 
in the colour of its venous blood very distinct. The sub¬ 
maxillary gland is supplied with nervous influence, from the 
cerebro-spinal system, by a nerve termed “tympanico- 
lingual,” which is apparently derived from the lingual branch 
of the fifth pair of nerves, its real origin being the chorda 
tvmpani of the seventh pair. From the sympathetic system 
the gland is supplied by branches derived principally from 
the principal cervical ganglion. The conclusions M. Bernard 
has arrived at are the following: 1. Whenever the tym- 
