Mr Budgett, Observations on Polypterus and Protopterus. 239 



for 24 hours in a landing net, with no more water than the 

 moisture of the atmosphere, and finally had to be killed. 



Polypterus may be watched for a considerable time, and give 

 the impression that it is a sluggish and inactive fish. If, howevei, 

 one is lucky enough to observe a male and female sporting 

 together, it will be seen that they are capable of wonderful 

 activity; executing the most lithe and supple movements, turning, 

 twisting, darting and pausing in an extremely graceful manner, 

 they thoroughly justify the native Mandingo name of Sayo or 

 snake-fish. 



The ovary of Polypterus is not hollow but originally a fold of 

 the ccelomic wall, it is early divided into compartments, both 

 longitudinally and transversely. Each compartment contains 

 from one to three ova, which are developed on the external wall 

 of the ovary. Later, the external wall becomes much plicated, 

 nevertheless at the internal and external summits of each fold 

 the ova retain their original position, being attached to the wall 

 of the ovary by the now pigmented pole. It thus comes about 

 that, through the internal wall of the ovary, which is a smooth 

 thin sheet, only the pigmentless poles of the ova are seen, while 

 through the external much folded wall only the pigmented poles 

 are seen. 



The attachment of the ovary extends backwards obliquely 

 across the short, thin walled and wide oviduct. The latter, about 

 3 inches in length in a 20 inch fish, opens to the exterior just 

 behind the vent. 



The spermatozoa in the male are extremely small ; not more 

 than ^ the diameter of a red corpuscle in length. 



It is seen then that both species of Polypterus found in the 

 Gambia migrate to the flooded lands to spawn ; that without 

 doubt Polypterus uses its air bladder as an accessory organ of 

 respiration and seldom as an hydrostatic organ, as a rule being 

 unable to float, though it should be mentioned, that, preparatory 

 to sporting near the surface, it was seen to take in several gulps 

 of air in succession. The spiracle is used for the emission of air 

 and not for the passage of water. The pectoral fins are important 

 organs of propulsion and not mere balancers, as in almost all 

 Teleostomes. 



b. The dry season habits of Protopterus on the Gambia have 

 long been known. Nothing however has been recorded hitherto 

 of their habits in the rainy season. 



Protopterus annectens emerges from its cocoon at the com- 

 mencement of the rainy season in the early part of June, the eggs 

 are usually ripe by the end of July. 



There is no certain sexual difference, even at the height of the 

 breeding season, except in old males in which the head is stouter 



17—2 



