DIFFERENT WAYS OF SWIMMING 



My trip was undertaken especially to visit this 

 crawl, to examine it closely, observe its working, and 

 the fish caught in it. Indeed the sight of its imprisoned 

 fish is an extraordinary one. Collected by the hundred 

 in a small space, covering only a few square feet 

 superficially, but big enough to allow the fish to move 

 about, the different species provide visible examples of 

 all the methods of swimming they have at their disposal. 

 These creatures, still full of life, over-excited by the 

 effects of the current which filters through their prison 

 net, dash about in every direction, try to find a way 

 out, displaying an unparalleled degree of animation. 

 The good swimmers of the open seas, sea perches, 

 mullets, and gilt-heads, move their pectoral fins and, 

 now and again, use their scull to give them a greater 

 impetus. Beside them are black congers; yellow- 

 spotted murry eels sliding about with a serpentine 

 motion. Not far away, a few soles raise themselves to 

 the surface by bending and rebending their bodies, 

 then down they go again. Near them, brill, shaped 

 much like them, but thicker and less flexible, support 

 themselves by little movements of their marginal fins, 

 and look like greyish plates floating in the water. 

 The most interesting are the skate and the eagle rays, 

 which, like birds that fly for long distances, swim by 

 beating the water with large fins extended like wings. 

 All these fish and others too, confined in their pen, 

 show, by the dissimilarity of their movements, the 

 extraordinary capacity of nature for varying its means 

 in order to obtain the same end. 



A few days later, I was to see a similar spectacle, 

 under more comfortable conditions, and in circum- 

 stances more favourable for careful and detailed study. 

 This was at the oceanographic station built by the 

 state of Tunis for the study of the sea and of fisheries 

 with the object of securing the best possible results 

 by methodical organisation. Situated on the shore, a 

 few miles from Tunis, it has the best possible situation 



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