110 REPORT OF Tin-: COMMISSIONER OF FISH AND FISHERIES. 



2. Arc the present generic references of some species correct and are 

 their structural characters accurately determined? While at present 

 the force of analogy is not so absolutely ov^ervvhelming as to justify a 

 positive assertion, I strongly suspect that species of genera now inde- 

 terminate will ultimately tend to range themselves in accordance with 

 the lines indicated: i. e., that species inhabiting gall bladders (Perugia's 

 ^^Myjcosporldium^^ cougri, for example) aviU be found to be referable to 

 uonvacuolate genera. 



GEOf;RAPHICAL AND SEASONAL DISTRIBUTION. 



Out of 70 species of hosts and 90 forms of Mi/xosporidia (true and 

 doubtful; species 7 to 102) localities are known for only 27 species of 

 hosts and 19 forms of Myxosporidia, and many of the localities are so 

 vague that they amount to little. In the hope that future descriptions 

 will supplement this glaring deficiency, a table is given showing all 

 the localities and dates of collection heretofore reported. 



The condition of the data as regards season is even worse than that 

 referrino- to locality. Eveu an approximate date of collection is known 

 in only about 25 per cent of the forms, and yet of all classes of data 

 this is certainly one of the most important. Many of the statements 

 are general in the e.xtreme (e. g"., " summer"), and in not a single instance 

 has the temperature of the water been recorded. 



Geographical and seasonal distribution. 



* The mention of this locality affords the only cliancc of an inferential correlation of this form >vitb 

 some one of the others known to live on the same fish. 



