238 Mr Budgett, Observations on Polypterus and Protopterus. 



contained ripe ova. P. lapradii, however, was taken 31 inches in 

 length, but females were crowded with ova when only 18 inches 

 in length. It would seem therefore that P. senegalus does not 

 produce young until it is practically full grown. 



In June and July sexually mature individuals were taken in 

 numbers together and the sexes were noted. It appeared to be 

 the case with both species that three-fifths of each lot taken 

 together were females. This discrepancy can scarcely be accounted 

 for by the greater activity of the males enabling them to elude 

 capture, for they were caught in shallow pools connected with the 

 river at high water. The water was baled from these pools when 

 the tide was low. 



When the fish are in the river they are always caught in the 

 shade of the river banks, up small creeks or under the bushes at 

 the sides of the river. For this reason it is almost impossible to 

 catch Polypterus in the trammel or seine-net, and with the cast-net 

 it is very difficult, for the habit of the fish is to spend much time 

 lying motionless on the bottom and it does not strike upwards 

 into the cast -net thrown over it as do most fish, but slowly 

 wriggles off, snakelike. 



Polypterus was watched in the wild state and also in captivity. 

 It lies for long periods in the mud at the river bottom with the 

 fore part slightly raised and resting upon its pectoral fins like a 

 seal upon its paddles. If the water is a little stale it may be seen 

 to move slowly forwards by the action of its pectoral fins, which 

 are worked very much as a lady uses her fan ; the ventral fringing 

 rays are deflected first, the more dorsally placed ones later, giving 

 the action, in which the whole shaft of the fin is involved, a 

 screw-like appearance. 



As it nears the surface, however, the whole of the body and 

 tail is brought into action, with a dart it strikes the surface, 

 gulps in the air with its mouth, lets out the excess by opening its 

 spiracles, and with lightning rapidity returns to the bottom. 



The only time Polypterus was seen to feed in the wild state 

 there was a small shoal of P. senegalus making their way slowly 

 along the river bank. One of their number seized a fresh-water 

 crustacean, two others gave chase and, stirring up the mud, they 

 all disappeared. When seizing young fry or tadpoles it proceeds 

 stealthily after them, propelling itself by the flutters of its fan- 

 like fins until within striking distance, and then with a sharp snap 

 they are gulped down. 



If the water is perfectly well aerated Polypterus may lie for a 

 long time without breathing air. But a specimen which had 

 been perfectly happy in tolerably fresh water for some days, when 

 allowed to reach the surface, succumbed in a few hours when 

 prevented from so doing. On the other hand one specimen lived 



