SUNIER: Marine fish-ponds of Batavia. 230 
Each time one kepala timah transferred from 
water of a salinity of 27.8°/,, into: 
aqua dest.\31.450/,,| 41.99/99 BE 62.99/59 | © 2 2.9 foo 
within 24 hours | | dead es, dead 
ET CN RATES | 
„ 2 X ” ” D 41 LOD 52 AS 
3 = 
” 3) 3 = 57.6°/ 
SIOE ORNE NE, Zu 2A 5a 
” 5 DS ” ” < dead 
” 6 x ” ” = 57.0°/ oo 62.9°/o9 5 
29 7 X 35 » = 
„ 8 x „ 32 
together in + 60/00, 
remained alive. 
The kepala timah that died upon being thrown into too concentrated 
fish-pond water, before expiring showed the following symptoms: 
The animals which were conveyed from distilled water into water of 
62.9°/,, salinity immediately floated about at the surface of the water, quite 
motionless, and that so high that part of the back from just behind the 
occipital spot to a little before the dorsal fin stuck out of the water, The 
dorsal and anal fins were not spread upright, but lay half folded down. 
The usual motion of the pectoral and caudal fins, which can always be 
observed, as described above, in a normal kepala timah standing still, was 
absent, the only motion observable being that of respiration. The occipital 
spot was not quite, but very considerably obscured. 
Sometimes the little animals so to say returned to life spasmodically : 
the normal movement of the pectoral and caudal fins was then exhibited 
for a short while, and the occipital spot brightened at once. But soon the 
motion of the fins dwindled, the spot also dimming again. After a while the 
little fish turned over and floated belly-upwards, upon which they soon died. 
These observations recall those of ISSEL (cf. NUSSBAUM-KARSTEN- 
WEBER (2%) pag. 501); this investigator observed on the Ligurian coast, 
how the Copepod Harpacticus fulvus fell into a lethargic condition as the 
concentration of the sea-water increased. This would keep on for days 
together; the animal only awaking from its lethargy when the concentration 
of the water had sufficiently decreased again. Also on transferring the aforesaid 
Copepod into freh water ISSEL saw a similar condition of lethargy developing, 
in this case however of a temporary nature. | have already communicated 
above that a strong temporary decrease is observable in the livelines and 
mobility of the kepala timah upon its being transferred from sea-water (in our 
case of a salinity of 33.4 °/,)) to distilled water, 
