62 Amenca7i Fisheries Society 



moment the floating townet is brought on board," while 

 in his "Resources of the Sea" he specially mentions "the 

 tax levied by jellyfish and Coelenterates generally upon 

 animals in the sea as high in the scale as fishes." Dr. 

 V. Hensen in 1883 claimed that "the small Sarsia tubu- 

 losa measuring only 11/2 centimeters eats fish eggs. I 

 had placed a small number of eggs with broken yolks 

 measuring on an average 1. 2 mm, in a glass vessel into 

 which a specimen of Sarsia had accidentally found its 

 way. Several were missing later and the gastric 

 chamber of the Sarsia was swelled out considerably." 

 The peculiar creeping jellyfish, the ambulatory gonozoid 

 of Clavatella prolifera discovered at Torquay, England, 

 by the eminent zoologist, Rev. Thomas Hincks, is de- 

 scribed by him as an agile climber at one time using its 

 suctorial discs as feet, and moving with ease up the per- 

 pendicular sides of a glass vessel, at another employing 

 them as hands, and climbing amongst the branches of 

 seaweeds. DeQuatrefages described an allied creeping 

 medusa Eleutheria which drags itself with diflficulty over 

 a smooth surface; but displays considerable activity as 

 soon as it reaches a tuft of sea weed. Eleutheria keeps 

 the mouth turned upward when it moves. Clavatella on 

 the contrary always carries it below. 



Now, it is well known that young fish live commensally 

 as boaders, so to speak, with some jellyfish. Many 

 observers have noticed this. Dr. Knut Dahl, indeed, 

 tells us that he saw in the Skagerrack, the pelagic young 

 of cod, haddock and whiting in great masses, drift past 

 under jellyfish at a speed of 3 to 4 knots. The sea was 

 quite full of jellyfish and under nearly every one of them 

 swam one or several young fish. All the jellyfish or 

 medusae are not so hospitable, and I have made a special 

 study of some cases of destruction of young fish by small 

 medusae. If, as I have reason to think, vast numbers of 

 these creatures devour fish as part of their food the loss 

 of young fish must be very extensive. 



