90 Proceedings of the Royal Society 
being developed. One long dorsal and anal fin without spines. 
u They are fresh-water fishes of the East Indies, and are able to 
live and move without the water for a short time, feeding on small 
animals.” “ It appears, from recent observations, that the amount 
of air which is in solution in water is not sufficient for the respira- 
tion of these fishes, so that they are obliged to come to the surface 
at certain intervals, to receive an additional quantity of atmo- 
spheric air.” 
The genus Ophiocephalus is distinguished by the presence of ven- 
tral fins. The species of this genus are common in India and the 
East; some of them, as the u Coramota ” or u Gachua v (the 0. gachua ) 
of Bengal, have excited considerable interest from making their 
appearance during the rains in unexpected places, and giving rise 
to the popular belief that they must have fallen with the rain from 
the clouds; the fish having left, for the time, the muddy waters 
where it resides, for the fresh wet grass, and the abundance of 
animal food it gets there. 
This genus was believed to be entirely confined to India and the 
East until Dr Gunther, in the year 1869. detected in the collection 
of fish made by Consul Petherick on the Nile one species which he 
has described as the O. obscurus. It was captured at Gondokoro 
on the Upper Nile, and forms the only exception yet known to the 
Indian habitat of the genus. 
The interesting fact of the great apparent correspondence of the 
fish fauna of the Nile with the distant rivers of West Africa was 
pointed out many years ago ; the fauna of the East African rivers 
being apparently somewhat different in character. Dr Gunther, 
from a careful examination of a number of species from the Nile 
and West African rivers, comes to the conclusion that — “the 
Faunas of the Nile and the West African rivers belong to the same 
zoological district; that there is an uninterrupted continuity of the 
fish fauna from west to east ; and that the species known to be 
common to both extremities inhabit also the great reservoirs of 
water in the centre of the African continent.”* 
It is, therefore, with some little interest that I am able to add 
this single species of Ophiocephalus found in the Upper Nile, to the 
* See Petherick’s “Travels in Central Africa,” vol. ii. London, 1869. 
Appendix, “Fishes of the Nile,” by Dr A. Gunther. 
