86 



salmon, of thousands of salmon fry, and of numerous trout and grayling, the 

 coarse fish being slightly affected. The fresh salmon just returned from the sea, 

 and invigorated with renewed vitality after their sojourn in salt water, and there- 

 fore in the perfection of health, were often attacked, and succumbed to the 

 disease, and it was not, tlierefore, necessarily the result of weakness, of disease, 

 or of injury. 



The disease has long been known in other rivers. Other, and somewhat 

 similar diseases to which fish fall a prey have also been recorded and scientifically 

 described. 



In 1844, linger published a description of a similar disease on carp in the 

 Botanical Gardens at Gratz. Trout and salmon breeders have, for many years, 

 observed the disease amongst their ova. 



Although it has been previously observed, the attention of the public seems 

 hardly to have been aroused to its serious ravages in our own rivers until the year 

 1877, when it was observed in the rivers Esk and Nith, which both flow into the 

 Solway Firth ; shortly afterwards it is reported from neighbouring ri\ers flowing 

 into the same Firth. In 1879, a serious mortality amongst the salmon is reported 

 from the Tweed ; and about the same time it is observed in the rivers in Ayrshire. 



It has been noted as a curious circumstance, that whilst no serious epidemic 

 has occurred in the rivers south of the Tweed, along our eastern coast, that the 

 disease has gradually extended thence upwards and downwards along our west- 

 ern coast from the borders, until at length this year (1883) it reaches the Wye in 

 Herefordshire. This raises suspicions of its being transferred by some means at 

 present undetermined. Mr. A. D. Berrington, in his recent report on the fish- 

 eries of the river Usk, states, that for many years it has been kno\vn to occur 

 occasionally in that river ; nor does it appear to have been unnoticed by the 

 netters on our own river Wye. It is jirobable that it did not assume the character 

 of an epidemic, and thus escaped public attention. 



A fevc recent records of the mortality from the disease, in rivers carefully 

 watched, present much interest and importance. The bailiffs removed 5,222 dead 

 and dying salmon from the river Tweed in the year 1880, 2,907 in 1881, and 

 14,627 in 1882, making in three years an aggregate total of 22,756 fish. In a 

 single year 2,000 fish have been removed from the Tay ; and nearly as many 

 for several years from the river Eden ; and also from the small river Esk. From 

 this last river 351 fish have been taken out dead in three days. The following 

 table shows the mortality amongst the salmon in the river Eden, where the 

 disease has been very carefully watched : — 



1,560 fish were removed in 1878 



422 „ „ 1879 



514 „ „ 1880 



409 „ „ 1881 



2,036 „ „ 1882 



1,177 up to the 31st May, 1883 



This disease is due to the invasion of the fish by a fungus, which is called 

 Sapro'xgnia ferax. This fungus is probably no new disease. It has existed with- 



