﻿386 The PhiUp2mie Journal of Science wm 



rossii the second white band is a third of the way down the palpi; in this 

 species (ludlowii) it is less, and the black intervening area is much smaller. 



James and Stanton (1912) list the two as distinct species. 



Stanton (1913) distinguishes the two species, but states that 

 Anopheles ludloivii is nearly allied to Anopheles rossii. 



Alcock (1913) describes the two species, but says that if it 

 were not for the fact that Anopheles ludlowii is said to transmit 

 malaria in the Andamans he would consider it a variety of 

 Anopheles rossii. 



Knab (1913) considers Anopheles ludlowii as a species closely 

 resembling, but distinct from, Anopheles rossii. 



Mr. Banks, entomologist of the Bureau of Science, considers 

 rossii and ludlowii as variations in one and the same species, 

 namely, Anopheles rossii. He states that this opinion is based 

 upon examination of the type specimens of these two forms at 

 the British Museum several years ago and that Theobald agreed 

 with him at that time that ludlowii was not a distinct species. 



All of the mosquitoes of the rossii-ludlowii group collected by 

 us, both from fresh water in Laguna Province and from brackish 

 water along Manila Bay in Rizal Province, have been of the 

 rossii type. Since these experiments were completed, one of 

 us (Barber) has collected in fresh water in Mindoro larvse from 

 which were bred an Anopheles with conspicuously spotted legs, 

 possibly ludlowii. Our experimental infections reported in this 

 paper have all been made with Anopheles rossii. 



Anopheles rossii is, according to the observation of Banks 

 (1906), Ludlow (1908), and ourselves, one of the most, if not 

 the most, prevalent and widely distributed anophelines in the 

 Philippines. This species may be found breeding everywhere 

 in water open to the sunlight, both in fresh water and in the 

 brackish or salt water of esteros along the extensive coast of 

 the Archipelago. It will even breed in stagnant water if run- 

 ning water is not available. We have found the larvae of this 

 species in the esteros along Manila Bay, in salt beds used by the 

 natives for evaporating sea water, in irrigated rice fields, open 

 rivers, the overflow from artesian wells, carabao tracks filled 

 with water, about water holes and troughs, carabao wallows, 

 and even in the foul water of tanks used to soak sugar-cane 

 stalks. 



The evidence of the ability of Anopheles rossii and Anopheles 

 ludlowii to transmit malaria is exceedingly contradictory. 



In India all investigators appear to be agreed that Anopheles 

 rossii, although one of the most prevalent species, is not of 



