74 TJiirty-ninlli .Imuial Mcct'uKj 



feel sure he has much in n-scrx c, and the way U\ l)ring it out is to liax'e 

 a free discussion. 



President: There is one tiiint; that 1 wouhl like to add a little later, 

 illustrating the wide spread of diseases which we have constantly to 

 face, fn the course of the discussion I would like to read a letter relat- 

 inti to a throat tumor atTecting hrook trout in California, hut 1 do not 

 think I should gi\e the name of my correspondent. 



AJK. Ch.\rle.s W. Burn ham: Do you know of any instances where 

 those diseases are communicated to the human race? 



President: T have seen newspaper statements to the effect tli.it cer- 

 l.iin iM'ench and German scientists believe and have perhaps so slated, 

 that in .\rgentina cancer has lieen transmitted from fish to the human 

 heing. 1 do not know whether these scientists are correctly quoted. 

 Certainly T have seen no statements in scientilk papers that cancer in the 

 luiman heing is derived in any way from eating or handling diseased 

 lish. 1 do not think that any scientist, at least in the United States, 

 is ready to say that thyroid carcinoiua in lirook trout, and which, hy the 

 way, attacks the brown and rainbow also, is communicable to man. 1 

 recently talked with one of the foremost students of cancer in the United 

 States, and I know that he will not make such a statement. He is sim- 

 ply trying to study the disease in the fish to discover, if he can, how it is 

 communicated from fish to fish, as it is, of course, very contagious, and 

 what it is in the water (because it is always communicated in water) 

 that introduces the disease into the fish. He begins to think that some 

 of the crustaceans may lie at the l)ottom of the whole trouble, hut he 

 has not so expressed himself as yet. 



Mr. I'r.xnk; N. Cl.\rk : This paper is very interesting. Referring to 

 Mr. r)Urnham"s question whether any disease may be transmitted to the 

 Inun.in race from fish, I want to say that I saw Mr. IM. C. Marsh inocu- 

 late himself with the Bacterium tnittac, which was killing thousands of 

 trout at .\orth\ille. He did not hesitate to take the chances, and it did 

 not harm him in any way. 



Xow, the diseases of fish differ ;it various places, especially with trout. 

 At Xorthville, for instance, we can raise brook trout up to fingerlings 

 2 or 2J/2, and occasionally to 4 or 5, without any difficult.v whatever. 

 By actual count and weight we raised this year 125,()!K) number 2 finger- 

 ling brook trout from 150,000 fry. 



On the first of July I had orders from Washington to put 10,000 

 of these fish in a pond. They were just as nice No. 2 trout as you ever 

 saw. Today, if you will count the live fish there, I guarantee that you 

 will not find 2.000, 80 per cent having died since the first of July. 



Now, we want to know what causes it. Why is it that at Northville 

 we can raise trout up to two inches with such excellent results, while 

 Mr. Bassett, at Paw Paw, Michigan, who is raising trout commercially, 

 has great difiiculty in growing them to that age or size? When once he 

 gets them past the No. 2 stage he markets 18,000 out of 20,000 at two 

 years old. He told me the other day that he had no difSculty whatever 

 after getting them past the No. 2 stage. At Northville it is just the 

 reverse; we grow them to the No. 2 or 3 stage, and they are then 



