122 NEW YORK ZOOLOGICAL SOCIETY 
as true and that the presence of parasites in the different biologi- 
cal organisms with which man comes in contact is becoming 
more generally known by their study, it is easy to see why so 
many ardent students are found to-be engaged in this interesting 
and fascinating work. Much already has been done in finding 
this material, but one may say that a mere beginning has been 
made in the study of its future effects on man. In fact, all or 
almost all of the germs that recently have been discovered as the 
causes of different diseases, are parasites or their products, and 
pathology is becoming largely influenced by a knowledge of this 
fact. 
To return to our immediate work at the Aquarium in New 
York and to the Zoological Park, I have to say that Dr. Townsend 
has been unremitting in his kindly endeavor to place at my dis- 
posal an immense amount of varied material which I have en- 
deavored to make as much use of as possible, and I wish here to 
thank him for his kindness and also for his intelligent endeavor 
to let me have such material as promised results of the first order. 
At the Zoological Park, too, Dr. Hornaday has hitherto allowed 
his assistants to place at my disposal such material as I thought 
would prove of interest and use to humanity, and I here wish to 
publicly thank him for his kindness since he thus recognized that 
it would not be his fault if my endeavors did not produce the 
results which he and the rest of us hoped would follow. 
I must not omit in this report, however, to thank Mr. Madi- 
son Grant for his unfailing response to any request I have had 
to make which he deemed consistent with the interests of the 
Society. 
I had hoped to be able to give a detailed account of the 
diseases and ravages of parasites among the fishes and animals 
that have fallen under my notice during the term of my position 
as pathologist, but as I am limited for space I must refer those 
interested to my numerous papers of the work done for the 
Society until I may have an opportunity to take up the subject 
as a specialty. 
Respectfully submitted, 
G. A. MACCALLUM, 
Pathologist, N. Y. Zoological Society. 
January. 1921: 
