Entozoa

a term which should, according ‘to its literal, meaning, include all animals which pa any period of their lives within the bodies of others not belonging to the same species. Thus the ichneumon, whose larva lives in that of the butterfly, the bot of the horse’s stomach, are Entozoa, like the tapeworm. But the term is now restricted to those members of the annuloid group which are commonly, known as worms. The transfer from one animal to another seems e ential to the proce which the preference for one organ or ti ue also subserves. The transfer from mice to cats, from dogs to sheep, from dogs to man, and _ the converse, are easily understood, both vegetable and animal food helping to carry the minute eggs or larve. The species of Entozoa are enormous. The conditions on which their multiplication depend are want of attention in the cleansing of food, contamination of water by the droppings of animals or the decay of their bodies; and, as regards the individuals an acid state of the secretions, such as accompanies strumous diseases, is e ential for their speedy multiplication.