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Parasitic Worms 
use in a number of diseases which owe their origin to specific organisms. 
The presence of these organisms causes the production of certain anti¬ 
bodies in the blood. It is then found that the blood serum gives 
a definite reaction with an extract made from the parasite. More than 
one variety of reaction can be made use of, but the most invariably 
successful is that known as complement deviation. No method is 
absolutely unimpeachable, but this one has been found correct to the 
very considerable extent of 90 °/ 0 of cases. A useful monograph and 
review of the whole subject has been written by Pfeiler (1911). 
Of a different nature is the work done by Tallquist (1907) on the 
anaemia produced by the presence of the broad tape-worm ( Dibotlirio - 
cephalus latus). This parasite occurs particularly in Finland and the 
adjoining region, although it is known in all parts of Europe and it 
gives rise to a very severe and fatal form of anaemia. In view of the 
fact that our present knowledge of the causation of anaemia is extremely 
limited, the work of Tallquist is of great importance. It is a widely 
accepted hypothesis that anaemia, in general, is caused by some 
poisonous substances finding their way into the blood and causing 
destruction of the blood cells or of the tissues from which they are 
formed. Tallquist’s work supports such a view in this particular case, 
for from the tape-worm he extracted poisonous substances which, when 
injected into the blood of healthy animals, caused marked anaemia. 
That is practically as far as he was able to go, but it represents a very 
material advance. 
Another matter which has received a very considerable amount of 
attention is the relation of worms to intestinal diseases in general and, 
in particular, to appendicitis, enteritis, typhoid fever and dysentery. 
The chief exponent of this line of investigation is Guiart (1910) who 
has brought forward a large amount of evidence together with not 
a little hypothesis in support of the view that intestinal worms may be 
the predisposing, if not the chief, cause of some of these diseases. 
Similar views have been advocated by Shipley (1909) in this country. 
They have been supported by a number of observations, chiefly in 
reference to appendicitis, and are to the effect that in cases of this 
disease thread-worms are frequently found in the appendix. The theory 
is that the worms injure the wall of the appendix and lead to the 
invasion of pathogenic bacteria. The most important and thorough 
contribution to this subject has been made by Garin (1911) who has 
found that the whip-worm (Trichuris trichiura ) damages the intestinal 
mucosa and is certainly responsible for a large proportion of cases of 
