PROCEEDINGS OF SOCIETIES. 
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Spallanzani, Lyngbye, Kutzing, Caras, N. V. Esenbeck, Agardh, Berkeley, Braun, 
and especially Unger, have each contributed to our knowledge of its natural his¬ 
tory, and recorded its most striking peculiarities. It has been recognised in Den¬ 
mark, Prussia, Austria, various parts of Germany, France, and the British Isles. 
The following are the chief synonyms by which it has been known :—Saprolegnia 
Ferox, Kutzing, Phycol, General; Conferva Ferox, Gruitbuisen, Nov. Act. Leopold 
Car. 1821; Byssus Aquaticus, O. F. Muller, Flora Dan.; Yaucheria Aquatica, 
Lyngbye, Hydr. Dan.; Hydronema, Carus, Act. Leopold. 1823; Saprolegnia Mol- 
luscorum, Achlya Prolifera, N. Y. Esenbeck; Leptomitus Clavatus, Prolifera and 
Ferox, Agardh, Syst. Algar. ; Leptomitus Piscicola, Berkeley. It is not uncom¬ 
monly found growing upon the bodies of flies and other dead animal substances 
which have fallen into water, especially in the summer months, and it is also well 
known to occur upon the bodies of living fish, and to produce a most destructive 
form of epizootic disease amongst them—a perfect plague of extremely contagious 
nature. M. Davine has described its baleful progress amongst the carp contained 
in a large pond in France. Hannover and Stilling also notice its appearing both 
amongst living and dead animals, growing, “avec une extreme rapidite,” and pro¬ 
ducing in the former illness followed by death. Unger likewise, in 1842, found sick 
Cyprini, with the plant fully developed upon them, in a pond in the Gratz Botanic 
Gardens ; and during the same year he asserts that the fish in the environs of the 
town were similarly affected, in so much, that mouldy fish, as they were com¬ 
monly termed, were often to be met exposed for sale in the public markets ; in one 
large pond all the fish were exterminated by its ravages, and in the reservoirs the 
thy male and trout also occasionally suffered. He says, “ It killed in about 48 hours ; 
few recovered which were once attacked ; it grew both on the body and the fins ; 
the fish lost their natural activity, sought the surface of the water, and seemed 
fatigued ; the plant extended from the mouth to the vent, like a covering of velvet; 
the scales at the point attacked loosened and fell off*; the parts affected were evi¬ 
dently enlarged, reddened, spotted with blood spots, and occasionally ulcerated; the fish 
appeared to move with pain, lay on their sides, or back, and these symptoms 
usually preceded death for only ten hours.” To complete its history, I may men¬ 
tion that it has been met upon dead flies (Goethe and Nees) ; on the dead larvse of 
the land salamander in water (Carus), of dead mollusca (Gruithuisen); on the 
wounded toes of the Triton Punctatus (Hannover) ; upon a wounded eel (St. 
Pierre) ; upon the eggs of Limax Agrestis (Laurent) ; and of Lymnsea Stagnalis 
(Valentin) ; upon both the ova and wounded body of Cyprinus Nasus (Valentin) ; 
upon the eggs of the stickleback (by M. Coste); and it is even stated that the cur¬ 
rent of water through their nests is probably intended to prevent similar occurrences. 
Valentin has also noticed it on the eggs of the Bufo Obstetricus; Pennant described 
it as it occurred upon roach kept in glass vessels, and it is well known to attack 
various species of carp, especially our well known favourite, the Cyprinus Auratus, 
or gold-fish. Of its occurrence on this animal we have a description by Dr. Bennett, 
in the Edin. Philos. Transactions. Finally, Kutzing has described three species 
(which I believe to be all identical), one of which is termed the Saprolegnia Xylo- 
phila, and found growing upon twigs in water. I too have likewise in my 
researches obtained it growing upon twigs, identical in its nature with his 
drawings, and ^ith the plant as it grows upon the bodies of living and dead gold 
fish, and derived originally from them. Further research on this subject has 
obtained for me the information that (what is probably the same plant) the Sapro¬ 
legnia Capitulifera has been observed by Alex. Braun (Rejuvenescence of Nature) 
to develop freely on decaying pieces of Nuphar pumilum, and also to attach itself 
to flies falling into the water in the localities where it thus grows on the plant. 
This plant (which fully deserves its name of Saprolegnia ferox), as it fell under my 
notice, occurred amongst a number of young gold fish (about twenty-five) kept in a 
parlour, contained in a round glass jar along with four young minnows. The gold 
fish had been obtained from the Botanic Gardens of the Royal Dublin Society, at 
Glasnevin, in September, 1855, having been bred there in the Victoria Lily House, 
during the previous summer months. They were of small size, varying in length from 
one to two inches; and as I had obtained them for the purpose of making a series of 
observations upon the changes which they undergo in colour during their growth, 
