428 MOSQUITOES OF NORTH AMERICA 



concerned has been furnished by the city council with a large circular, which, in 

 addition to information as to the cause and spreading of malaria, contains advice 

 as to the best means of destroying the malaria mosquitoes. 



" Certain dates have been specified between which the houses are to be searched 

 and the mosquitoes destroyed. At the expiration of the time specified inspectors 

 appointed by the city council will visit each house and apartment and make 

 careful examinations to see that the work of exterminating the mosquitoes has 

 been properly carried out. Those who fail to comply with the regulations 

 promptly and thoroughly will be subject to a fine of about $7.50." 



WORK ALONG RIVER FRONTS. 



Communities living along navigable rivers may have good anti-mosquito work 

 hampered by the constant reintroduction of mosquitoes from boats landing at 

 their river fronts. This point has been especially noted in the course of the 

 excellent work done under the direction of Dr. Andrew Balfour at Khartoum on 

 the Blue Nile. The following passage is taken from the First Eeport of the 

 Wellcome Eesearch Laboratories, pages 31-23 : 



" At an early period the steamers were found to be largely infected, especially 

 with the larvae of Stegomyia fasciata, and to a less extent by those of Culex 

 fatigans. Anophelines, either as larvae or imagines, have never been met with ; 

 but up-country, as will be noted later, the adults are frequently to be seen on 

 board, and may remain as passengers for a considerable period. At first it was 

 decided to use lime for the steamer bilges, but this was said, erroneously I be- 

 lieve, to act upon iron and to be unsuitable. Consequently crude petroleum was 

 recommended, though not so good nor so easily applied. Along with this the 

 periodical emptying of the bilge and fumigation with the sulphur squibs de- 

 scribed by Colonel Giles were advised, the latter to get rid of the adult insects. 

 Unfortunately in the case of the steamers familiarity had evidently bred con- 

 tempt, for, at first, despite the co-operation of the Director of the Steamers and 

 Boats Department, little energy was displayed by the engineers in charge, and 

 the preventive measures were largely ignored, and in some instances even 

 ridiculed. This was the more to be regretted as there is no doubt that mos- 

 quitoes can be banished from all the steamers if a little care and trouble were 

 taken. Mr. Beadnell, of the Geological Survey, carried out these simple methods 

 on the S. S. ' Nubia,' and practically cleared her of mosquitoes, so that for the 

 first time he was able to sleep below in comfort. A great improvement also 

 resulted in the case of the gunboat ' Zafir,' in which I went to Dueim and found 

 to be simply swarming with adult Culices and their larvae, while these measures 

 absolutely prevented any mosquitoes breeding out on board the S. S. ' Amka ' 

 during a period of nearly two months, the greater part of which was passed in 

 regions swarming with these winged pests. Latterly, I am glad to say, the 

 engineers have been impressed with the necessity of doing all in their power to 

 aid the brigade. This is the more necessary as it is easy for the steamers to in- 

 fect the town and thus spoil much of the work done and render it futile." 



