PROCEEDINGS OF SOCIETIES. 17 



Spallanzani, Lyngbye, KutziiiK, Carus, N. V. Esenbeck, Agardh, Berkeley, Brauni 

 and i'speclally Unper, have eoch contributed to our knowledge of iU natural his- 

 tory, and recorded its most striking; peculiarities. It has been recognised in l)eo- 

 mark. Trussia, Au'itria, various parts of Germany, France, and the British Isles. 

 The following are the chief synonyms by which it has been known :— Saprulegnia 

 Ferox, Kutzing, Phy col, General ; Conferva Ferox, Gruithuiscn, Nov. Act. Leopold 

 Car. 1821; Byssun Aqiiaticus, O. F. Muller, Flora Dan.; Vaucheria Aquaticflf 

 Lyngbyo, Hydr. Dan. ; Hydronema, Carus, Act. Leopold. 1823; Saprolegnia Mol- 

 luscoruro, Achlya I'rolifera, N. V. Esenbcck ; Leptomitus Clavatus, Prolifera and 

 Ferox, Agardh, S^st. Aljrar. ; LepUunitus Piscicola, Berkeley. It is not uncom- 

 monly found growmg 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 contagions 

 nature. M. Daviue 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 rupidite,'* 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 oiten 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 moilusca (Gruithuiseu) ; on the 

 wounded toes of the Triton Functatus (Hannover) ; upon a wounded eel (St. 

 Pierre) ; upon the eggs of Limax Agrestis (Laurent) ; and of Lymnaea 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 f^din. 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 with the plant as it grows upon the bodies of living and dead gold 

 fish, and derived originally from them. Further reseturch on this subject has 

 obtained for mo 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 yt)ung minnows. The gold 

 fish had been obtained from the Botanic Gardens of tiie Royal Dublin Society, at 

 Glasnevin, in September, 1855, having been bred there in the Victoria Lily Uottse, 

 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 makiug a series of 

 observations upon the changes which they undergo in colour during their growth, 



