626 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XVI. 



Wing ornamentation is the same as in the female. The legs are faintly 

 banded at all the joints. Fore ungues are unequal and uniserrated. 



Larva. — Head is black, thorax dark, brown in centre, paler at the sides, 

 abdomen is dark brown. The antennae have no spine on outer side. Fronial 

 hairs simple and unbranched. 



Palmate hairs are present on 2-7th segment inclusive ; there are undeveloped 

 hairs on the 1st segment. The blade is long and dark, the shoulder serrated 

 and the filament long and pointed. 



Egg (Fig. 3) is boat-shaped, with a narrow striated frill extending all round the 

 margin of the upper surface. The float is lateral, extending nearly to each end, 

 but nearer the narrower. It does not encroach on the frill. The ova are as 

 a rule laid in the early morning on the surface of some floating object. They 

 are laid in irregular groups and only display star-shaped and other patterns 

 when disturbed by the wind or current. 



Habitat and Observations. — A. arabimsis has been found from Sheik Othaman 

 to D'thala. It is the common anopheles of the district and is the chief and, 

 as far as the writer can say, the only certain malaria transmitter in nature. It 

 loves breeding in running water and is found in all the small streams and 

 irrigation channels round about Lahej. It has also been found breeding in 

 wells. In most parts of the country water is obtained from deep wells, 40-50 

 feet below the surface. 



Adult females were found in the tents of the rest camp at Sheik Othaman 

 in February 1904 and in January 1905 larvae were found breeding in the 

 irrigation channels in the garden of the Resident's bungalow. A careful search 

 was made for larvas in June to September, but neither adult imagines nor 

 larva? were found. It is most probable that it comes into season early in 

 November and remains till April or May. This almost exactly corresponds with 

 the fever season at ^heik. 



The same can be said about Bir Said Ali, where it breeds in the local wells. 

 Many adult females were caught in the tents in February 1905. 



It abounds in all the pools and streams around Lahej and Salim, where 

 there is much cultivation. The tents occupied by the sepoys at Salim 

 contained large numbers of this mosquito in September, January and 

 February. Nobat has long been famous for its fever and it was found that 

 this anopheles, though present in the Wady Tiban practically all the year 

 round, is most numerous from March to ^November. It breeds in the wells at 

 El Milleh during the hot weather. It was found in the wells around Sulek and 

 Ulub ; it was at the latter place in May 1904 that this anopheles was found for 

 the first time breeding in the well near Ulub. The water was stored in tanks 

 in the camp and all precautions were taken from preventing any larvae from 

 Hardeba being brought to the camp and placed in the tanks. I personally 

 inspected the tanks immediately after the water was brought. Adult females 

 were caught every morning in a tent nearest to the Ulub well (900 yds.). 

 One morning the sepcy in charge informed me some larvae were brought in the 



