On a Simulium-larva from a mountain-current 
of the Gunung Pangerango. 
(Summary). 
(Continued from Vol. LXXVIII, Fasc. 1, page 40). 
In my preceding paper I uttered the hope of being able 
one day to ascertain with the living animal and in nature 
the anchoring of the clinging-organs in a lock of silk 
previously secured by the larva to the substratum. In August 
1918 [ had the opportunity of observing a number of 
Stmulium-larvae immediately after taking them from their 
natural surroundings through a binocular microscope in a 
glass disk filled with water. This observation proved that 
in moving, the head was first pressed against the substratum 
for some time before fixing the front clinging-organ, during 
which the mouthparts were moved briskly. It was moreover 
evident that the hind clinging-organ was never fixed 
anywhere but close to the previously-fixed front clinging- 
organ the latter letting loose again after the hind clinging-organ 
had been anchored there. 
The newly produced silk proved so colourless and transpa- 
rent that [ did not succeed until after a considerable time 
with a certain position of the mirror in which only little 
obliquely entering light was let through and with the use 
of the object-set and the Huycens-oculars no. 3 (Zeiss) 
in clearly observing after the releasing .of the hind clinging- 
organ the lock of silk in which this clinging-organ had been 
fixed a moment ago and especially the traces left by the 
hooks of the clinging-organs in that lock of silk. When I 
had once seen this I afterwards succeeded every time without 
