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young may remain outside the body of the host and still 
survive ? 
(f) How do the different forms gain entrance to the body? 
(g) What are the different stages of development, metamorphosis? 
(h) At what stage or stages is the parasitic action exerted? 
( i) By what method does it become located in a particular organ 
or structure, its migrations in the body? 
ACTION OF THE PARASITE 
What is the pathogenic effect of the parasite upon the host? 
In what way is the particular species injurious outside its direct or strict- 
ly parasitic action? 
Does the parasite carry infection directly or indirectly? 
LESIONS 
What structural changes and lesions result from the presence of the 
parasite, its method of feeding, its migrations, and forms of growth? 
What lesions are typical of the parasite? 
What is the pathology of the lesion after the parasite has left? 
What must be considered in carrying out steps in the differential diag- 
nosis of lesions? 
SYMPTOMS, TREATMENT AND PREVENTION 
These are points upon which there are differences of opinion as 
to just where the final word should be said. Some are of the 
opinion that these points should be covered in detail by the in- 
structor giving the work in parasitology, • while others are of the 
opinion that this phase of the subject should be dealt with in 
Theory and Practice (medicine). Granting that local conditions, 
especially in regard to the teaching staff of the different veterinary 
colleges, might call for some variation, it is generally felt that in 
some one study some particular instructor shall ,give in detail and 
emphasize the importance of the clinical symptoms. It would 
seem only logical that this should be left to the man teaching clin- 
ical medicine. In Therapeutics and Sanitary Science, for example, 
we see no reason why other than mere mention of the form .of 
parasitism to be dealt with is necessary. The students already 
have or will have information regarding parasites from their stud- 
ies in Parasitology. The instructor, for want of time, if for no 
other reason, must accept the student’s information or assume that 
it will be acquired later ; certainly he should not attempt to give it. 
On the other hand, the time allowed to the study of animal para- 
sites does not permit of a complete and thorough discussion of 
symptoms, treatment, and prevention, and the man teaching the 
subject is as a rule not especially prepared to do this. Finally, it 
seems only logical that this should be dealt with by the teacher of 
Theory and Practice on the same basis that he would discuss the 
symptoms, treatment and prevention for other diseases. 
