V THE INTERNATIONAL FISHERIES EXHIBITION 211 



Dutch coast two Dutch naturalists, Dr. Hoek and 

 Dr. Horst, have within the past two years made some 

 careful studies of the oyster which have very greatly 

 added to our knowledge of that important mollusc, 

 and may eventually be of service to the oyster- 

 culturist. The results obtained by these observers 

 are shown by large coloured drawings exhibited in the 

 Netherlands department. 



Some results of zoological science coming under 

 the third head, viz. Special Biology of Economic 

 Fishes, are to be found scattered here and there in the 

 Exhibition. Collections of insects injurious to fresh- 

 water fish or to their eggs and young, are exhibited 

 in the Swedish Court, also, in a small way, in the 

 American Court. A few parasites of fishes are ex- 

 hibited by Dr. Cobbold, in the Eastern Arcade, and a 

 remarkable series of the crustacean parasites, or fish- 

 lice, of the fishes of Trieste is shown by Dr. Antonio 

 Valli in the Austro-Hungarian section. Fish diseases 

 are represented by stuffed specimens of salmon, with 

 cotton wool attached, indicating the position of the 

 growths of Saprolegnia which cause the malady 

 known as the ' salmon-disease/ 



The fourth section into which we have divided 

 the results of zoological science, as seen in the Exhi- 

 bition namely, that of the various developments of 

 Pisciculture is richly represented by the exhibits of 

 English oyster -culturists and salmon farmers; but 

 in the most interesting way in the American depart- 

 ment, where the devices made use of for hatching 

 the eggs of sea-fish are shown. I need hardly say 



