53 



the central and northern portions of the country, reaching up to 33° 

 south latitude ; the intermediate zones lies to the south of the former 

 and separates it from the inmiune territory. Dipping is the recognised 

 remedial method. 



SWELLENGREBEL (N. H.) & SwKI-LENGREBEL - DE GrAAF (J. M. H.). 



On the Requirements of different Anophelines in Regard of the 

 Abode of their Larvae. — Meded. Burgerlijk Geneesh. Dienst 

 Ncderl-Indie, Batavia, 1919, no. 7, pp. 39-85, 1 chart. 

 In a previous paper [R.A.E., B, vii, 97] the authors stated the three 

 premises on wliich the practical value of the specific distinction of 

 Anophelines is based. The third premise is that different breeding- 

 grounds are necessary to the various species and this point is dealt 

 with here. For the purpose of enumerating the breeding-places the 

 mosquitos have been divided into salt-water species, hill species, 

 species not hmited to distinct bounds, and shade-preferring species. 



Salt-water species. On the coasts of Java and Sumatra the 

 dependence of Anopheles ludlowi on salt-water is quite pronounced. 

 This dependence on distinct breeding-places is still more marked 

 in the valleys with fishponds in N.W. Sumatra [R.A.E., B., vii, 99], 

 which is remarkable in that the change from salt-water to the fresh 

 water ponds would seem greater than from the ponds to a marsh 

 watered by them and in which many other Anophelines breed. Some 

 observations appear to show that unfavourable conditions in the 

 salt-water breeding-places may force A. ludlowi to inhabit water 

 with no brackish taste. This and other facts point to caution in 

 holding that A. ludlowi is hmited to a distinct area. The destruction 

 of recognised breeding-places may cause tliis species to use others 

 that were previously neglected. Attention is drawn to an observation 

 made by Schiiffner about 20 years ago, when several examples of 

 A. ludlowi obtained from the coast escaped in the course of some 

 experiments and deposited eggs in a fresh- water pool inland. Breeding 

 continued for some generations and then ceased. The presence of 

 coastal A. ludlowi in fresh water does not therefore necessarily mean 

 that its larvae have become quite independent of salt water and this 

 also holds good for A. ludloivi from inland fishponds. A. rossi (by 

 which is meant the form with larvae hke those of A. ludlowi, with 

 long posterior clypeal hairs and long lateral clypeal hairs) has a 

 distribution corresponding somewhat to that of A. ludlowi, but does 

 not posses the latter's partiahty for special breeding-places. For 

 instance, where A. ludlowi disappeared from certain fishponds from 

 October, A. rossi remained in undiminished numbers. In the munici- 

 pahty of Samarang, A. rossi has been found in the low lands, at the 

 foot of the hills and in the lulls, and this in rice-fields, dirty water 

 ditches, clear running brooks with algae, small marshes at the foot 

 of the hills, briok reservoirs devoid of vegetation, and fresh water in 

 a boat. The places farthest inland were about 4 miles from the 

 coast and at about 300 feet altitude. 



Hill mosquitos. A. maculatus was found regularly near hills and 

 mountains, but never occurred at any great distance from them, 

 even in clear, running water. Breeding-places include foot-prints, 

 fishponds, rice-fields, swamps, reservoirs, buffalo wallows, etc. It 

 is almost as httle fastidious as A. indefinitus and A. Jcochi, but only 



