122 
SPOLIA ZEYLANICA. 
Young Anabas not only consume the larvae, but will swallow the 
entire egg-rafts, each comprising about 160 eggs. On June 4, ‘ ‘ lula ” 
fry of the seventh day after hatching were observed to ingest a 
quantity of separate white mosquito eggs floating on the surface of 
the water in a glass dish. Here it may be mentioned that on the 
same day about 30 «‘ lula ” surface hatchlings from another brood were 
eaten up by older “ madaya” fry. Later on it was found that the 
‘ ‘ lula ’ 5 fry would approach the culicine rafts, but would not eat them; 
as soon however as the minute larvae hatched out from the eggs, 
\ the fry devoured them. Since then I have fed my £ ‘ lula ” fry with 
abundant mosquito larvae, without always observing the actual 
process of ingestion. 
Top-minnows (Cyprinodontidae) are represented in Ceylon by one 
or two species of Haplochilus , of which the commonest is H. lineatus, 
called “ diya pita hendeva ” in Sinhalese. They lay eggs which 
become attached by glutinous threads to water plants, about as large 
as ■“ lula” eggs, with pale amber-coloured yolk containing a number 
of oil-globules. I have not found them so attached, but have seen 
them freshly extruded in July. The vitelline membrane shows a 
reticulated sculpturing, and the long adhesive threads radiate from 
a centre placed near the oil-pole. The mature fish attains a length 
of about H inch; the snout is flattened and shovel-shaped, adapted 
for surface feeding ; the male is larger than the female, exhibiting at 
the breeding season a bright golden green lustre on the scales of 
the hind-body ; ventral and anal fins greenish, the latter with back- 
wardly prolonged orange-coloured rays and three black basal flecks ; 
dorsal and caudal fins and lower lip orange ; hind-body without the 
6-8 vertical black bars which are present on the spawning female. 
Maimed mosquitoes dropped upon the surface of the water are 
seized and swallowed by the top-minnows. These fishes ( H . lineatus) 
possess a flashing white occipital triangular spot, which can be alter¬ 
nately darkened and rendered invisible by the expansion of black 
pigment cells, and can again flash out resplendently when these 
contract. It is not phosphorescent; I think that it acts as a lure, 
but have not been able to prove that it does. 
Explanation of Plates II. and HI. 
Ophi omphalus striatus. 
Fig. 1. — Egg with single large oil-globule, floating below the 
surface film of water, as seen with a simple lens. 
Fig. 2.—The same seen from the upper pole under a low power. 
The small spherules inside the large globule appeared with a deep 
focus, m, vitelline membrane ; v, yolk ; o, oil-droplet. 
Fig. 3. — Egg seen in suspension about fifteen hours later; e, 
embryo. 
