2.-THE MYXOSPORIDIA, OR F80R0SPERMS OF FISHES, AND 

 THE EPIDEMICS PRODUCED BY THEM. 



By R. E. Gurley, M. D., 

 Assistant, U, S. Fish Commission. 



TABLE OF CONTENTS, 



Page. 



Introduction 65 



General description of tlie Mtixosporidia... 71 



I. Nomenclature and detinitiou 71 



II. Mor j)hology 73 



General description of structure. . 73 

 Detailed description of individ- 

 ual structure H 75 



m. Zoological position 93 



IV. Distribution 100 



V. Classitication 112 



VI. Pathology 117 



VII. Microscopic technique 119 



Vlir. Definitions 120 



IX. BiblioCTaphy 123 



Descriptions of genera and species 135 



Tabular key to species 138 



Non-myxosporidian species 166 



Species more or less probably myxo- 



sporidian " 181 



True Myxosporidia 190 



Page. 

 Description of genera and species— Cont'd. 



Ordo Cryptocystes 190 



Family Glugeidse 190 



Genus Glugea 191 



Genus Pleistopliora 394 



Genus Thelohaiiia 195 



Ordo Phajnocystes 205 



Family Myxobolida; 206 



Genua Myxobolus 206 



Family ChloromyxidEe 258 



Genus Chlunmiyxum 259 



Subgenus Sphaprospora 265 



Genus Ceratomyxa 274 



Family Cystodiscidse 278 



Genus Cystodiscus 279 



Genus Spbajromyxa 282 



Family Myxidiidie 283 



Genus Myxidium 283 



Explanation of plates 291 



Index I-V 



INTRODUCTION. 



Up to the present time very little attention has been paid to the 

 diseases of fishes, and to their parasites from the standpoint of the 

 effect produced by themupon the host. Yet there can be no doubt that 

 a knowledge of such diseases would be of great practical value. Any 

 one who considers the proportions that fish epidemics may attain will 

 hardly be inclined to question the utility of searching investigation in 

 this direction. Thus, to take a single instance, in the epidemic of 1884 

 in Lake Mendota, Prof. Forbes^ states that: 



It was estimated that fully 300 tons had died up to that time. On August 7 the 

 Madison Transcript reported that 200 tons had been hauled away by the city 

 authorities during the four weeks preceding and that the fishes were still dying. 



Epidemics of similar extent have been reported in Europe. 



The important results in the way of prevention of epidemics among 

 domesticated animals and cultivated plants obtained as the result of 

 scientific investigation afibrd some ground for the hope that similar 



' Bull. U. S. Fish Com. for 1888 (1890), viil, p. 482. 



p c 92-^^ — 5 



65 



