SUNIER: Marine fish-ponds of Batavia. À 279 
mosquito-production, were more favourable in proportion as the salinities 
were higher, at least as long as they remained below 70 °/o. 
Hence it seems to me not impossible that the unfavourable influence 
exerted on the /zdlowi-production by the rise of the salinity above 24.9 0), 
was counteracted by a number of other influences conducive to a high 
productivity, and is therefore not very strongly expressed in the averages 
behind A and a in Table XI. 
Other important figures are those after AB and A’B’ in Table XI 
denoting the /zdlowi-production expressed in percentages of the rossii- 
production, firstly for the females captured in mosquito-nets, and secondly 
for the females emerged from the larvae and pupae that were caught. These 
figures, the method of calculating which I have already explained in detail, 
are derived from Table IX, in which the Anopheline totals for the several 
10 °/ and 5 %/o9 salinity classes have been collected and further elaborated. 
The figures placed behind AB and A’B’ in Table XI tally remarkably 
well. They only deviate rather importantly for the salinities between 20 and 
24.9 0/5. A glance at Table IX however accounts for this; for during the 
prevalence of the salinities just mentioned nets were indeed set in the 
ponds near Heemraad which produce so many /udlowi, but no larvae and 
pupae were collected in these ponds. Apart from this the almost exact 
correspondence of the figures after AB and A’B’ relating, in the same 
order, to the female mosquitos caught in the nets and to those emerged 
from the larvae and pupae collected, speaks for the reliability of the 
material collected by Mr. VAN BREEMEN and me. It proves at all events 
that the staff of the Batavia Public Health Service (Gezondheidsdienst) made 
few errors in determining the mosquitos in spite of the fact that, at least 
to me, it seems often rather difficult to u en the /zdlowi and the 
rossit individuals from each other. 
The fact that also in the case of the figures after AB and A’B’ in 
Table XI the greatest /udlowi-production corresponds with salinities between 
10 and 19.9°/, and not with salinities below 10 °/oo is accounted for by 
the same explanation given above for the parallel fact regarding the averages 
placed after A in Table XI. For indeed both the figures appearing after 
AB and A’B’, and the averages recorded after A were directly calculated 
from the whole of the data collected in the entire Batavia empang region. 
Table IX affords me little occasion for further observations. What this 
Table has to show is after all better expressed in Table VII. I have already 
explained before how Table IX only represents an attempt to cast the 
figures collected by the Public Health Service (Gezondheidsdienst) as to 
the /udlowi females emerged from larvae and pupae captured, which figures 
were not directly mutually comparable, into some shape which would 
allow of some measure of comparison. 
It only remains for me to point out in a few words that it appears 
from Table IX (and Table V) that from larvae and pupae collected at the 
