534 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Those zoospores werepyriform iu shape during the short time they were 

 observed iu motion ; on becoming stationary the cilia disappeared, being 

 probably withdrawn into the body of the spore, which then assumed a 

 globular form. This change took place in a very short time — not ex- 

 ceeding ten miuutes — and Avhile under observation minute projections 

 became visible on the eiige of the spore, which grew into delicate fila- 

 ments of considerable length. I have succeeded iu fixing the develop- 

 ment of the fungus in this state, and it can be seen in ^'arious stages of 

 growth, all of which were ciliated spores within the space of one hour. 



This, the asexual mode of propagation, is remarkable for the rapidity 

 with which it is accomplished. A few of those ciliated spores become 

 attached to any part of either a healthy or a diseased fish ; in one hour 

 the cilia will have disappeared and a filament of somfe length will have 

 ^jirouted from the spore. Thus, in a single day, a fish on which no fun- 

 gus coidd be discerned is to-morrow seen to be affected, and in three 

 days is spotted or patched over with fungus from head to tail. 



In the second or sexual mode of i^roduction of spores a short pedicle 

 is i)ushed out from one of the sides of a filament, on which a globular 

 sack — oogonium — is formed, and within this sack a number of oospores 

 are produced, which are spherical in shape and have a cell- wall or en- 

 velope, and some are provided with a nucleus in the center. These, af- 

 ter impregnation, escape from the oogouia, and are probably capable of 

 living in the water for an indefinite period, in a dormant or resting state, 

 until the conditions arise which ai-e favorable for their germination. 



It may be asked, how does the fungus affect the fish, and do any re- 

 cover from its effects "? The fungus produces a local irritation and in- 

 flammation of the integument, as is evidenced by the congestion and 

 even ecchymosis of the true skin, by abrading of the scales, and in the 

 more advanced stages by ulceration and sloughing, affecting the whole 

 thickness of the integument and mucous surface. 



Wherever the fungus adheres and spreads, the function of the skin is 

 necessarily interfered with. Light, which is so essential to the fish in 

 promoting its pigmentary secretions, is cut off from a large portion of 

 its skin. Eudosmosis, exosmosis, and the secretion of the mucus for 

 lubrication are destroyed, and in this way constitutional symptoms would 

 be occasioned which, if the disease continued, lead to the death of the 

 fish. 



The second question, "Do any fish recover from fuugus attack ?" may 

 now be answered more hopefully. The fisliermeu and watchmen on the 

 Tweed report having seen several fish with new skin growing over the 

 sores upon their bodies, from which this fungus had disappeared, and I 

 am inclined to believe that this is so. A male kelt has been sent to me 

 by Mr. List, which was taken in tidal water below Berwick bridge. 

 This fish is 2 feet in length, and weighs about 3 or 4 pounds ; it is 

 supposed to have been affected with fungus, and to have completely 

 recovered from its effects. No particle of fungus could be found upon 



