80 Thirtieth Annual Meeting 



appropriation to build a new liatehorv, and they have not started 

 it yet. 



Prof. Marsh : I would like to ask the gentleman who spoke 

 about Connecticut if he noticed in those fry that he was talking 

 about, the ap})earance of the dead ones. Did they look like 

 healthy fry ? 



Mr. Mathewson : Tliev appeared to be perfectly healthy. 

 They seemed to start and go all at once ; I took them to the state 

 chemist at Yale college and he could not explain it. 



Prof. Marsh : You examined the dead fry and their sides 

 and muscles seemed to be all right? 



Mr. Mathewson : Yes, except a little dark streak through 

 the intestines. 



Prof. Marsh: Xo ulcers or sores? 



Mr. Mathewson : Xo. 



Prof. Marsh : That might have been a different disease than 

 the particular one that we are discussing. 



Mr. Mathewson: This was just as they were beginning to 

 feed — they had been feeding about two weeks at that time. 



Mr. Geer : I would like to ask if that disease would affect 

 the hatching troughs also so as to kill the fry ? 



Prof. JMarsli : We have had the disease in fry that were in 

 troughs, but very mvich more rarely than in the ponds. Thi&i 

 summer for the first time it occurred in the troughs. The 

 troughs in the house, as far as protection from germs is con- 

 cerned, are on just the same basis as cement ponds out of doors. 

 They are painted with asphalt all over and are perfectly imper- 

 vious. So I explain their infection on the ground of original 

 and rare infection from the springs, and that should be excluded. 

 If you could continue impervious construction up into the spring, 

 it would l)e advisable to do so, Init you cannot do it, so that once 

 in a while this disease will attack trout even in cement pondh 

 under the best conditions, but you can nip it in the bud, whereas 

 with wooden or earth ponds the infection is carried on forever; it 

 rests in the organic material, soaks into the wood, and multiplies 

 in- this organic matter which always exists, and disinfection is 

 impossible. But in the cement ponds disinfection can be readily 

 accomplished, and yo\i can start over with your pond perfectly 

 clean. X^ow if this oriuinal infection should occur every vear 



