246 TREUBIA VOL. II, 2--4. 
attention had once been drawn to this I afterwards frequently saw female 
Haplochilus javanicus swimming about bearing clusters of eggs about the 
genital opening. 
But these egg-clusters invariably disappeared soon, i.e. a couple of 
hours after their presence had been noted. Examination of the eggs still 
hanging down from the genital opening of the female always showed, 
that these eggs had only just begun to develop, i.e. they were at the 
stage represented in fig. 23. Older eggs a little more developed I only 
found among the algae. I have not had the opportunity to make out whether 
the eggs simply happen to get entangled here and there among the 
algae, or whether the females actively try to transfer the eggs to the algal 
filaments. 
As reported before, SEYMOUR SEWELL and CHAUDHURI (°°) also 
mention that the female of Haplochilus melastigma (MC. CLELL.) is known 
to carry her eggs about with her in clusters of 30 to 36 attached to the 
abdomen behind the ventral fins. On a female Maplochilus javanicus 
measuring 31 m.m. (inclusive of the caudal fin), I once counted 24 eggs, 
hanging in a cluster from the genital opening. 
With the kepala timah this carrying along of eggs already produced 
outside the body does not occur. 
In the case of Haplochilus panchax it is not difficult to fertilize artifi- 
cially the eggs taken from a female, so that they develop normally. 
Females bearing ripe eggs are recognized when looked at from above, 
i.e. from the dorsal side, by the bulging of the flanks behind the pectoral 
fins. Such a female is laid on her back on a towel and then held by the 
head between the thumb and index of one hand and by the tail between 
the same fingers of the other hand. Next the thumb and index holding 
the head-end are moved along the animal’s sides towards the genital 
Opening, gently pressing the body. Upon this the eggs, in the first place 
the ripe ones, will spring from the genital opening. These eggs which 
by their adhesive threads stick to everything should then be taken from 
the genital opening, with a fine pincette and deposited in a clean dry 
china bowl. 
Next one takes a big male in which the clear blue colour on the 
caudal and dorsal fin has completely developed, also squeezes it in the 
manner described above and then passes the genital opening of the male 
a few times over the eggs still lying dry in the china bowl. Then water 
is poured into the bowl with the eggs. I always took for this the water 
in which the animals had lived whose eggs and seminal fluid had been used. 
After five minutes this water was again poured off from the eggs and 
replaced by another quantity of the same water. This renewing of the 
water I repeated once again after another five minutes. Upon this I separated - 
the eggs which were clinging together by their adhesive threads, by means 
of a couple of needles under the binocular microscope, and I put them 
