274 Proceedings of the Royal Physical Society. 



of Africa — the P. palmas. In answer to inquiries, I am 

 informed that several new species are at present in the 

 collections of the British Museum, and were taken, I under- 

 stand, in the river Nile. Some six species, or so, will there- 

 fore include all that are known as belonging to the Genus 

 Polypterus, and they are all natives of the fresh w r aters of the 

 great continent of Africa. 



All the species of the genus appear to bear a very strik- 

 ing resemblance to each other. They have the body elon- 

 gated, full and rounded in front (about the region of the 

 pectoral fins), a little behind the head ; and from this part 

 it becomes more compressed in character laterally, and 

 rapidly diminishes in breadth until it terminates in the 

 rather broad caudal fin. 



The largest species are found in the river Nile, the Bichir 

 being described as measuring, when fully grown, some 2 

 feet or more in length. It has no less than sixteen dorsal 

 finlets, and these commence at but a short distance behind 

 the head. The P. Endlicheri, from the White Nile, has 

 twelve of these dorsal finlets, beginning apparently at a 

 slightly greater proportional distance behind the head. 



The West African species, the P. senegahis, appears to 

 be smaller in size, and with fewer dorsal finlets, which are 

 ten in number, beginning also at a slightly greater propor- 

 tional distance behind the head. While the P. palmas, 

 from Cape Palmas, on the coast of Guinea, still farther to 

 the south, and almost in the same latitude as Old Calabar, 

 is a fish of 9 T 3 o inches in length, has only seven dorsal 

 finlets, and these begin at a much greater proportional 

 distance behind the head than in the other species, being- 

 only a very little in front of the middle of the fish, measur- 

 ing (in the published figure) from the snout to the extremity 

 of the caudal fin. 



The two specimens offish now exhibited from Old Calabar, 

 although in many of their general characters they agree with 

 the characters of the Genus Polypterus, have the body much 

 more elongated, and cylindrical in its form, and show, pro- 

 portionally, less of the flattened or laterally compressed 

 character, as in all the species of Polypterus. It is in this 



