THE CARPS 33 



fact noticed by Graliam is that this fish has ceased to behave as a 

 Cyprinoid, and lias become entirely a plankton-feeder. Its name 

 has an obvious reference to its habits and appearance, Engrauli- or 

 anchovy, Cypris or carp, that is to say, an anchovy-carp, that 

 recalls the habits of a Clupeoid fish, but is really one of the carp 

 family. To quote the Report, " so far as the evidence goes this fish 

 resembles the Clupeoid fishes in its pelagic or open water habitat, 

 as well as in its structure. We frequently observed Engraulicypris 

 apparently catching Copepods and other members of the 

 plankton near the surface. Their stomachs contained Cladocera 

 or Copepoda." 



" Tliis is an interesting example of fish belonging to a typically 

 river family, the Cyprinoids, taking on a very different form, where 

 the conditions resemble the sea, especially in the abundance and 

 stability of a rich population of plankton, and adopting not only 

 a pelagic existence but the shape and form of a pelagic family." 

 The resemblance to marine fish does not end here ; " some floating 

 segmenting eggs in the plankton, which evidence seemed to prove 

 were those of Engraulicypris, were found," and this fact is com- 

 mented on " as so far as I know this is the first record of a floating 

 egg in a fresh- water fish." 



On exposing the brain of this fish it was at once apparent that 

 no facial lobe was to be seen in the usual position, not even a small 

 one as is found in the roach group. 



It was also found that the external appearance of the brain of 

 a bleak was very similar to that of Engraulicypris, and we shall be 

 able to show that these fishes have the same pattern of internal 

 brain structure when they are examined by microscojDical methods. 

 My first observations on the bleak were made during a visit to the 

 Lake Annecy. Both in this Lake and the Lake of Geneva the silvery 

 scales were used for the manufacture of artificial pearls. This 

 industry has almost died out as the Japanese culture of artificial 

 pearls has driven it out of the market. I noticed a mass of bleak 

 lying on a fishmonger's slab at Annecy, which was strikingly sug- 

 gestive of a number of smaU herrings lying in a mess of blood- 

 stained mucus with detached scales. In turning over the pages of 

 the " Complete Angler," I was struck with the following jjassage, 

 " The Bleak or freshwater Sprat, a fish that is ever in motion at the 

 top of the water, ought to be much valued though we want Allomot- 

 salt and the skill of the Italians to turn them into anchovies." 

 Both the sprat and the anchovy belong to the herring family so 

 that it was apparent to Isaac Walton that the bleak was similar 

 in appearance to the jDlankton-feeding Clupeoids. 



