76 Miscellaneous Intelligence. 



have as much as two square feet of its skin thickly covered with 

 Saprolegnia. If we allow only 1,000 fruiting hyphae for every 

 square inch, we shall have 288,000 for the whole surface, which, 

 before, gives over 10,000,000 spores for a day's 



ugh to provide a spore to every cubic foot of i 

 ) feet wdde and 5 feet deep and f< 



} and 5 feet deep and four mile- lung 

 Forty such diseased salmon might furnish one spore to the gallon 

 for all the water of the Thames (380,000,000 gallons per diem) 

 which Hows over Teddington Weir. But two thousand diseased 

 -a! mon have been taken out of a single comparatively insignificant 



It will be understood that the above numerical estimate of the 

 productivity of Saprolegnia has been adopted merely for the 



-ake of illustration ; that 1 do not intend to suggest that the 

 zoospores are evenly distributed through the water into which 

 they are discharged by the zoosporangia : and that allowance 

 must be made for the very short life of those zoospores which do 

 not speedily i*each an appropriate nidus. Nevertheless, the con- 

 clusion rem:;: •siin thai every diseased salmon 

 adds immensely to the chances of infection of those which are not 

 diseased." 



The author shows that the hyphas penetrate the true skin, but 

 obtained no evidence that they "breakup into toruloid segment- 

 (as in the ease of Eutputu ,/m's.v/], and thus give rise to general 

 septic poisoning <»r fungoid metastasis." The epidermis is de- 

 stroyed, and its place is taken bv a thick, felted mycelium, which 

 entangles the minute parliclc- Mt' sand that are suspended in the 

 water, and this no doubt constitutes a verv irritating application 

 to the sensitive surface of the true skin/' ' Death results without 



IV. MlSCELLJ 



BiUiographiege, 



