MICROSCOPE AND AGRICULTURE 



mildew for example, has a large number of threads 

 running from its winter spheres and each thread is 

 terminated by a little group of branches. The sacs 

 which fall from the opened sphere in the spring, 

 only contain four spores in this case. 



The animal enemies of the farmer, so far as they 

 concern the microscopist are more difficult to study. 

 Many of them are internal parasites and to gain 

 a real knowledge of their habits and life histories 

 necessitates a good deal of rather unpleasant work 

 for which the ordinary microscopist has neither the 

 time nor the inclination. 



In order to give our readers some idea of this 

 work, let us take one of the commonest of all agri- 

 cultural parasites and trace its life history whilst 

 giving hints for its examination under the micro- 

 scope. The common liver fluke is a worm which, in 

 the adult stage, frequents the liver of some domestic 

 animal, usually the sheep. A friendly butcher will 

 probably be able to supply us with a specimen and, 

 when we receive it, we shall probably dub it a very 

 unwormlike creature. The worms form a large 

 class in the animal kingdom and they do not 

 all resemble the earthworm by any manner of 

 means. 



The liver fluke is a flat, almost leaf-like creature, 

 it is not ringed like the earthworm and, under the 

 microscope, we can plainly see all its internal 

 organs. The fluke lays its eggs, each one enclosed 

 in a little capsule, in the liver of the sheep. They 

 are carried to the intestines and finally set free 



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