72 SCIENCE PROGRESS 
kinase-plasma does not readily clot when treated with thrombo- 
kinase. Moreover, Wooldridge some years ago pointed out 
that kinase-plasma could be easily coagulated by the addition of 
peptone-plasma. The plasmata obtained by injection are there- 
fore dissimilar in many respects; in peptone-plasma an anti- 
thrombin predominates, in kinase-plasma an anti-kinase. 
9. SUBSTANCES WHICH DIRECTLY HINDER COAGULATION BOTH 
INSIDE AND OUTSIDE THE Bopy 
Substances such as hirudin, which is the active principle 
secreted by the salivary glands of the medicinal leech, a similar 
body obtained from the heads of other blood-sucking worms, 
such as ankylostoma caninum, as well as the virus of many 
thanatophidia, together with anti-bodies, such as those described 
by Pugliese! and extracted by him from the blood and almost 
every organ of the body except the brain, directly check the 
coagulation of blood both inside and outside the organism. 
The anti-body or bodies are, according to Pugliese, chiefly 
obtained from the liver, kidneys, and muscles. They are not 
destroyed by heat, but are diffusible. His results may be easily 
seen in the following table: 
Clot. 
Plasma 4- Anti-bodies + Ca. =o 
” 7 ” + H,O ee 
ue + ‘i + Serum = + 
a = . + Kinase = + 
It would seem therefore as if both anti-kinase and anti-thrombin 
were capable of being yielded by nearly all the tissues of the 
body. The inner coat of arteries, which might have been expected 
to form anti-bodies during life, have, however, been shown by 
Loeb? to yield no anti-bodies of any kind. 
The term “hirudin” was introduced by Jakoby and Franz. 
This substance appears as yellowish scales soluble in water 
with a slight turbidity, and the activity of the solution is not 
destroyed by boiling. Its activity is such that a definite amount, 
ool gr., will maintain 7°5 cc. of blood fluid outside the body. 
The researches of Fuld and Spiro show that hirudin can 
undoubtedly neutralise thrombin both within and outside the 
? Quoted from Centralbl. f. Physiologie, 1906. 
? Virch. Archiv, clxxvi. 1904, and Hofmeister’s Beitrige, v. 1904. 
— Cl. 
