102 
Mr Budgett , The Habits and Development 
The Habits and Development of some West African Fishes. 
By J. S. Budgett, M.A. 
[Read 4 February 1901.] 
Our knowledge of the fish fauna of the fresh waters of Africa 
has of late been greatly extended by the study of collections from 
the great African lakes, the Nile, and the rivers of the West 
Coast. Up to the present time, however, nothing has been known 
about the breeding habits and development of any of the most 
interesting forms, including Polypterus, Protopterus, Gymnarchus, 
Mormyrus and Heterotis. It was with a view to investigating 
the development of these fish and especially of Polypterus that 
I spent the summer of 1900 on McCarthy Island on the river 
Gambia. The flooded lands of this island I searched persistently 
from June to September, but failed to obtain the eggs of Poly- 
pterus ; I did, however, obtain a very young larva of Polypterus 
measuring ljinch in length. 
In this larva the dermal bones are not yet developed over the 
general body surface, though some of the dermal bones of the 
head have already begun to ossify. The dorsal finlets at this 
stage are merely a continuation forwards of the finfold of the tail. 
The heterocercy of the caudal fin is scarcely more apparent (even 
in section) in this larva than in older specimens. The external 
gill is of very great size. The base of the shaft is situated 
immediately behind the spiracle, and is supported by a short 
segmented rod of cartilage borne upon the hyomandibular 
bar. Each pinna of the external gill bears a double row of 
pinnules. Alternate pinnae on each side are smaller and directed 
at a different angle of the intermediate pinnae, giving the appear- 
ance of two rows of pinnae on either side. The internal gills 
are very small and can as yet be of little functional importance, 
as the combined section of the arteries to the internal gills is 
certainly not a tenth part of the section of the artery supplying 
the external gill. The arteries to the two halves of the swim- 
bladder are likewise very small indeed. In this young larva the 
roof of the mouth is perforated by a duct from the pituitary body, 
as has been shown to be the case in Calamoichthys 1 . The oviduct 
appears to develop in a similar manner to that of Lepidosteus 2 , 
1 Bickford, Elizabeth E., “ The Hypophysis of Calamoichthys,” Anat. Anz. x., 
1895. 
2 Balfour and Parker, “ The Structure and Development of Lepidosteus,” Phil. 
Tr. Roy. Soc. London , Part ii., 1882. 
