SUNIER: Marine fish-ponds of Batavia. 233 
the big yellow eggs showing through the back on both sides of the 
vertebral column. 
In many Cyprinodontidae the females are larger-sized than the males. 
It would appear to me that with the kepala timah the case is rather the 
reverse. Certainty on this point of course could only be obtained by a 
great number of measurings. 
In BREHM (#) it is already pointed out that the dorso-ventral compres- 
sion of the anterior half in contradistinction to the latero-median compression 
of the posterior half of the body, as well as the hind-ward situation of 
the dorsal fin betray that the kepala timah is a real surface fish. The animals 
are indeed frequently seen hanging just under the surface of the water by the 
head which is flattened on the upperside. The caudal end of the body then 
hangs down a little so that the dorsal fin still remains under water. When 
a kepala timah stands still in the water it holds its tail curved either 
to the right or the left. This is connected with the fact that when standing still it 
always causes a downward and hindward current of water (to remove the 
respiration water taken in by the mouth and expelled by the branchial 
apertures) by the motion of the pectoral fins. By this motion of the 
pectoral fins the animal would be propelled if it did not neutralize the effect 
of this motion by that of the caudal fin of the bent tail. 
The kepala timah remains alive a fairly long time on the dry. When 
just drawn out of the water it takes fairly long leaps by flapping its tail. 
Soon, i. e. after a few minutes or somewhat sooner it leaves off doing 
this and then lies quietly, only occasionally taking a couple of short leaps. 
When I took a number of kepala timah out of the water, gently dried 
them with a towel and then allowed them to lie quietly under a glass 
dish, putting some low object under the rim of the dish so as to make 
ventilation possible, all the little fishes remained alive at least three hours. 
If restored to the water again within those three hours they began to 
swim again at once; and the occipital spot, which as I have mentioned 
previously, dims at once when a kepala timah is taken out of the water 
regularly turned clear white again within one or two seconds. 
The little fish which had lain dry for three hours in my laboratory 
_ mostly had the caudal fin more or less dessicated and stuck together, 
so that at first the animal had some difficulty in swimming, the caudal 
half of the body showing a tendency to sink. Also the pectoral fins were 
sometimes rather dried up at the edges after three hours out of the water. 
These fins would then recover but partly after the animal had been swimming 
about for a while, and so remained more or less damaged. 
Much longer than three hours the kepala timah could not hold out dry. 
After 3'/, hours two out of five had died, the three others being still 
able to swim. After 3'/, hours only one big individual out of three was 
still alive. On being put in the water however, it floated belly-upward, 
only one of the two pectoral fins making faint movements; but ten minutes 
