Moore. — Study of Trout Diseases. 75 



g-anism, the malarial parasite, challensred the best efforts of 

 Laveran, Ross, Grassi and others during a period of twenty 

 years before the facts associated with malaria were under- 

 stood, and the simple remedy of a dose of quinine could be 

 prescribed at the appropriate interval after a chill. When 

 pressed to speed up results in the study of Octomitus for their 

 quicker application to practical fish culture, a cheerful refer- 

 ence to this fascinating bit of history proves an effective 

 anodyne in allaying a natural impatience for results. So I 

 beg your indulgence. 



^ In the further study of Octomitus the efforts of the Com- 

 mission have been directed this current year to the following 

 phases of the problem : 



1. The examination of wild brook trout waters to deter- 

 mine whether the organism is indigenous to our native brook 

 trout. 



2. The examination of wild waters flowing from infected 

 hatcheries to determine the seriousness of infection in the 

 wild state. 



3. To continue the life history studies of the organism, 

 mcluding an investigation of the possibility of transmission 

 of the organism through the eggs of "carrier" brood fish. 



The question — Is the germ, Octomitus, indigenous to our 

 native brook trout? — is not easy to solve. I do not claim to 

 have solved it yet, I am merely attacking the problem. One 

 mode of approach has been by the study of wild waters which 

 for a long period of years have contained only brook trout. 

 Two such waters within the boundaries of New York State 

 have been located and studied this summer. They offer ex- 

 ceptional advantages for the pursuit of this question for the 

 following reasons : 



(a) The lakes orginally stocked with native brook trout 

 have been isolated from other fisheries waters for a long period 

 of years. Natural dams, which in later years have been raised 

 somewhat, have kept out fish of various species inhabiting the 

 waters below, particularly the brown trout, which have been 

 introduced into the region in more recent years. 



(b) The lakes have been practically self-sustaining. 

 There appears to be one record only of the introduction of 

 "new blood" in these waters and this occured in both lakes 

 about ten years ago. To one lake there was a shipment made 

 >f eyed eggs from a Pennsylvania brook trout hatchery and to 

 the other, eggs from a New Hampshire trout hatchery. 



(c) A small hatchery exists on each lake whereby the nat- 

 ural increment of increase has been augmented by hatching a 

 certain number of eggs each year from the lake spawners 

 and planting them back in the lake as fry or fingerlings. In 

 this connection the hatchery itself, with its necessarily arti- 



