THE LIFE HABITS OF POLYPTERUS. 
NOR: HARRINGTON. 
a. Living (Resting), b. Feeding; c. Swimming; d. Breathing ; e. Reproduction. 
REFERENCE has already been made to the occurrence of 
Polypterus in the Lower Nile (Sczence, Vol. V, 1898, Oct. 23, 
p. 54, and 1899, March 3, p. 315). The purpose of the present 
paper is to give a number of additional notes as to the occur- 
rence and habits of this interesting and little-known fish. These 
details are treated in the following order : 
Polypterus bichir differs but little in its habits from the other 
fresh-water fishes of the Nile. It lives in the deeper depres- 
sions of the muddy river bed, but it is an active swimmer and 
not essentially a bottom-liver or a mudfish. It is most active 
at night time when it is in search of its food. 
Feeding. — Trawl lines were largely used as a means of col- 
lecting. They were laid late in the afternoon and left set all 
night. In the early morning, by three or four o’clock, besides 
many other large fish, a few Polypteri would usually be taken. 
Sometimes, however, specimens would be taken during the 
early morning in the second going-over of the trawls. Aside | 
from small siluroids, Armoot, Bayad, Schilbe, Schal, which 
were commonly used as bait, Polypterus eats a great many 
other teleosts, as is evidenced by the more or less undigested 
remains in the stomachal pouch of such forms as Cyprinodon, 
Anguilla, and Chromis. It apparently catches them alive, for 
it prefers live bait and always swallows its food whole. 
Although catfish are usually taken head first, some fish were 
found in the stomachal pouch in a reverse position ; their 
undigested remains are probably ejected through the mouth. 
The pouch is admirably adapted for resisting the very danger- 
ous and strong spines possessed by all the catfishes. 
On account of the great vitality of the siluroids they probably 
remain alive for some time after they are taken into ve digestive 
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