REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXXIX 



During the winter of 1891-92 niucli trouble was experienced with 

 the eggs of many of the rainbow tront at the ISTeosho Station, Mis- 

 souri, which, when extruded from the females, were hard and fully 

 rounded, falling into the receiving pan like shot, and failing to 

 become fertilized by contact with the milt. The same ijeculiarity 

 had also been observed previously at other stations. Prof. C. E. 

 Kiley, of Drury College, Missouri, who examined the eggs while the 

 stripping was still in progress, was inclined to attribute their abnor- 

 mal condition to the presence of many minute organisms discovered in 

 the fluid which issued with them from the ovarian openings. Dr. Gur- 

 ley, however, who was prevented from visiting the station at that time, 

 but who was furnished with a series of the eggs preserved in alcohol, 

 discredits this view and has suggested two other possible causes, 

 namely, prematurity on the part of the spawners, which were only 

 twenty months old, and inflammation of the ovaries. 



Mr. W. F. Page, superintendent of the IS^eosho Station, does not con- 

 sider either of these explanations satisfactory, as rainbow trout from 

 five to nine years old have furnished eggs of the same character in the 

 past, and the fish in question had been stripped this year for the first 

 time, so that inflammation could not have been produced in them from 

 excessive handling. 



The solution of this question must, therefore, he left until another 

 opportunity occurs to study specimens affording the hard eggs during 

 the spawning period. 



Dr. Gurley has now in course of preparation a comj)lete review of 

 the extensive group of protozoan parasites termed Myxosporidia, 

 which infest fishes and also some other kinds of aquatic animals, and 

 are sometimes the cause of great mortality among them. No syste- 

 matic revision of the group has yet been published, and the descrip- 

 tions of the different forms are mainly scattered through the pages of 

 various journals. Such American species as can be obtained will be 

 discussed from a study of the fresli material. 



COLLECTIONS, PREPARATION OF REPORTS, ETC. 



The quarters assigned to this division for laboratory x)urposes in the 

 Central Station of the Fish Commission at Washington are no longer 

 adequate to meet the increased requirements of the work, and addi- 

 tional space is much needed. This want is mainly felt in respect to 

 accommodations for special biological and physical inquiries, which are 

 now so poorly provided for as to greatly retard their progress, while, 

 at the same time, the demands for information based upon such studies 

 are becoming more urgent every year. There is also insufficient stor- 

 age space for the large collections constantly arriving from the several 

 vessels and field parties, which are now performing pr;ictically con- 

 tinuous service during all seasons. Although it is not intended to 

 retain from these collections more than a small type series, to serve for 

 the identification of species, yet, owing to the slow progress necessarily 



F O 92 IX 



