40 PREVENTIVE AND REMEDIAL WORK AGAINST MOSQUITOES. 



half a cent, whereas 2 pounds of sulphur per 1,000 cubic feet would 

 cost 6 cents. Moreover, it is pointed out that in practical work on a 

 large scale the expense and trouble of hauling the disinfecting equip- 

 ment from one place to another would be greatly diminished. He 

 concludes that while mercuric chlorid can not altogether take the 

 place of sulphur, it has a hitherto unrecognized effect, especially with 

 reference to flies and mosquitoes. 



APPARATUS FOR CATCHING ADULT MOSQUITOES. 



In his important paper entitled ''A Preliminary Account of the 

 Biting Flies of India,"" Mr. H. Maxwell-Lefroy, imperial entomolo- 

 gist, describes an interesting apparatus which he used to catch mos- 

 quitoes in his bungalow. In an account published in the United States 

 Daily Consular and Trade Reports,^ Consul-General William H. 

 Michael, of Calcutta, mentions this apparatus, stating it to be an 

 invention of Mr. Lefroy. In his own account, however, Mr. Lefroy 

 does not claim it as his invention. 



He used a wooden box, lined with dark green baize and having a 

 hinged door; the trap was 12 inches long, 12 inches broad, and 9 

 inches deep; a small hole, covered by a revolving piece of wood or 

 metal, was prepared in the top of the box, and tin was placed on the 

 floor inside. Owing to the habits of mosquitoes to seek a cool, shady 

 place in which to rest, such as a dark corner of the room, or bookshelf, 

 or something of the sort, they will enter this trap, which is put in the 

 part of the room most frequented by mosquitoes, all other dark 

 places being rendered uninhabitable, so far as possible. Mr. Lefroy 

 writes : 



My room being open to the veranda, hordes of mosquitoes come in, and as the room 

 is lined with bookshelves there are many desirable sleeping places. The trap stands 

 in a shady corner, and a large number of mosquitoes enter it when they come home 

 in the morning; the rest are usually driven out of the bookshelves either with a duster 

 or a little tobacco smoke. Finding this desirable sleeping place untouched, they 

 go in; the door is then slammed and fastened. At the top of the box is a small hole 

 with a movable plate to close it; through this a teaspoon ful or less of benzene is intro- 

 duced and the plate put back. After a little time all the mosquitoes are dead. The 

 box is taken to the veranda and opened there till the fumes of benzene escape. 



In this way in thirty days Mr. Lefroy caught 2,336 mosquitoes — a 

 daily average of 83.75; daily average of females, 22.68. At the 

 same time 23 of the biting sand flies of the genus Ceratopogon 

 were caught. He further states that whereas the inmates were 

 before disturbed with mosquitoes and sand flies, which especially 

 attacked the baby, the pest practically entirely ceased. All of the 

 mosquitoes were not exterminated, but so large a portion was 



a Bui. No. 7, Agricultural Research Institute, Pusa, India, pp. 12-14, 1907. 

 &Dept. Commerce and Labor, Bureau of Manufactures, p. 10, March 3, 1909. 



