68 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 



(c) Describe important and constant structures before unimportant 

 and inconstant ones. 



(d) Describe structure before function. 



Tbe principal exception is the chanj^e of place of the cyst, wliicli for 

 convenience is placed before the myxosporidium. Properly (were 

 arrangement an end rather than a means) it should follow the myxo- 

 sporidium. But the cyst occupies quite a subordinate (almost, so to 

 speak, an accidental) position in the life cycle, and it sheds little light 

 upon any of the structures either of the adult or of the spore. Further, 

 to i)lace it between the myxosporidium and the spore would make an 

 awkward break in the continuity of the life-history. 



The following is the order adopted, based upon the principles given: 



I. Synonymy: 



a. Recognized binomial name, au- 



thority, (late. 



b. Synonymy prior to recognized 



naine, in i)areiithesi8. 



c. Relerence to proposition of recog- 



nized name, followed by sub- 

 sequent synonymy. 



II. Cyst: 



a. Formation. 



b. Structure. 



(1) Macroscopic (form, size, color, 



etc.). 



(2) Microscopic (a) structure and 



origin of membrane and {b) 

 contents. 



III. Myxosporidium : 



a. General characters (form, size, 



color, etc.). 



b. Ectoplasm. 



c. P^ndoplasm : 



(1) General description. 



(2) Nuclei. 



(3) "Granules" and ''globules." 



(4) Vacuoles. 



(5) Inclusions, notably pigment. 



d. Pseudopodia. 



e. Anioj bold movements. 



IV. Spore formation : 



a. Formation and segmentation of 



pansporoblast. 



b. Development of sporoblast into 



spore (in same order as descrip- 

 tion of spore, below). 



V. Spore: 



a. (Jeneral description (form, size, 



tailed or not, etc.). 



b. Shell: 



(1) Ph ysi CO- opt ico-chemical 



characters. 



(2) Valves, position and separa- 



bility. 



c. Tail. 



d. Capsules: 



(1) Number, position, etc. 



(2) Filaments. 



e. Sporoplasui: 



(1) Form. 



(2) Nuclei. 



(3) Vacuole. 



(4) "Granules" and "globules." 



VI. Exit of sporoplasm, and couijiletion 



of life cycle with earlier stages of 

 development of myxosporidium. 



VII. Haliitat; seat, season, frequency. 



VIII. Pathological anatomy: 



a. Morbid structures (in order of 

 formation 1 : 



(1) Cell infection. 



(2) Tnmors. 



(3) Ulcers (Later stage of tumors). 



IX. Effects and symptoms. 



X. Epidemics: 



a. Fishes affected ; territory cov- 



ered ; extent of ravages. 



b. Causes. 



(1) Predisposing or contributory: 



(a) Age, etc. 



(b) Pollution of streams. 



(2) Exciting: Mode of infection. 



Further, were it not for the abundant evidence to the contrary, fur- 

 nished by the literature, it would seem superfluous to urge that every 

 report should contain, at least, the following data: 



Host. — The place and date of collection, the water-temperature, the 

 scientific name ^ of the host, together with the age (or size) of the latter, 



' Upon this last point too much stress can not be laid. The habit of recording the 

 host merely by the jiopular name (often local, always more or less ambiguous, .and 

 not infrequently designating a whole genus) is greatly to be deprecated, as identi- 

 fication is rendered difficult or impossible, especially for students of other times and 

 countries. 



