93 



This may be due to the unsuitability of the carrier for this Plasmodium, 

 or to the fact that mature schizonts (which in quartan malaria before 

 sporulation strikingly resemble gametes) were mistaken for gametes. 

 In a second series of experiments the authors satisfied themselves 

 that at least some of the parasites showed flagellation and the better 

 results achieved may perhaps be due to this fact. 



In obser^'ations for determining the natural index of infection, 

 A. ludloivi proved to be the most important transmitter. A. rossi 

 and A. rossi indefinitus were slightly infected, the former more than 

 the latter. This agrees with Barber's experiments. A. sinensis was 

 seldom infected. The infection of A. harhirostris varied ; in the 

 first period of obser^T-ation it was slight, but during the second period 

 liigher than in A. ludlowi, though too much importance must not 

 be attached to this increase owing to the small number (33) of speci- 

 mens examined. The negative results with A. aconitus contradict 

 Stanton's observations on the natural infections of this species. It 

 was free from infection in villages where A. sinensis, A. harhirostris 

 and A. indefinitus were infected as well as A. ludloivi. A. aconitus 

 therefore appears to be pernicious in some countries and not in others. 

 Whether Anophelines with a low natural index shovild be neglected 

 i? a question that is not answered In any case the natural index 

 indicates the species against which the first measures should be directed. 



SCHUFFKER (W.), Sw^ELLENGREBEL (N. H.), SwELLEXGREBEL DE GrAAF 



(J. M. H.) & MocHTAR (A.). On the Biology of Anopheles (M.) 

 iudloici in Sumatra. — Meded. BurgerUjk. Gexeesk. Dienst. Nederl- 

 Indie, Batavia, 1919, no. 3, pp. 65-88, 5 plates. 



In those districts of the Dutch East Indies where endemic and 

 epidemic rhalaria have been studied Anopheles ludloivi appears 

 to be the principal carrier and to be easily infected with both the 

 malignant and benign tertian :^orms ; nothing definite is yet known 

 regarding the quartan. It is a well-defined species both in the 

 larval and adult stages, the larvae being easily recognised by the 

 length and position of the cl}'peal hairs. A. ludlowi is a house-mosquito. 

 In Java it has been known to fly about 1,100 yards from a dwelling 

 in search of a breeding-place, while in Sumatra flights of half that 

 distance have been definitely ascertained. It would appear that this 

 species may remain in one and the same house more than one night 

 and one day. In inland localities it does not bite out of doors, though 

 on the coast it does so. It is only found in inhabited houses. A. lud- 

 lowi apparently requires a rest after feeding and is generally found in 

 the morning near its victim. In a bed-room the proportions of ^. ludlowi 

 to other mosquitos caught was as 1 to 1. In the large front veranda 

 of the same house the figures were ■2-^ and 10, these figures indicating 

 the proportions as between the species and as between bed-room and 

 veranda. In a cow shed the figures were 1| and 3, and 6 and 10 in a 

 buffalo shed. The bite of A. ludlowi is less painful than that of 

 Culicines. As it is not easily disturbed when feeding, a painful bite 

 that attracted attention would lead to its destruction. It is very 

 voracious and keeps on sucking after its stomach is filled. At the 

 same time it defecates, first a clear liquid and then the ingested blood, 

 which may possibly have undergone some change. Should numerous 



