MOSQUITOES, SILKIVORMS, AhID DRAGON-FLIES 9 



three hundred and fifty species, or different kinds, of mos- 

 quitoes are known, nearly fifty of which are found in North 

 America. Besides the irritation caused by their "bite," 

 i.e., piercing with the sucking beak, it has been proved 

 that mosquitoes are the conveyers and distributors of the 

 germ of malarial fever. Only certain kinds of mosquitoes, 

 however, are malaria-carriers. These all belong to the 

 genus Anopheles ; most of them may be distinguished 

 by the possession of spotted wings, while the innocuous 

 kinds have the wings clear. There are a few innocuous 

 or non-malarial kinds with spotted wings, however, but 

 no malaria-carrying kinds with wholly clear wings. Other 

 kinds of mosquitoes are almost certainly the distributors of 

 the germs of yellow fever, and the same kinds convey a 

 terrible tropical disease called elephantiasis. 



The most effective remedy against mosquitoes is to 

 pour a little kerosene on the surface of the pool in which 

 the larvae and pupae live. The kerosene will spread out 

 and form a thin, oily film over the surface of the water, 

 and no winged mosquito will be able to emerge alive 

 through this film, contact with kerosene being fatal to 

 almost all insects, and especially so just after a moult. 



For a full and excellent account of the life of mosquitoes 

 see " Mosquitoes," by Dr. L. O. Howard. (See page 327 for 

 list of reference books with publishers' names and price.) 



SILKWORMS 



How to get silkworm eggs. — Live eggs of the silk- 

 worm moth, Bombyx viori, are regularly sold by dealers 

 in Japan,* and sometimes can be got in curiosity shops 

 in this country. They may also be obtained wherever 

 there is a silkworm-rearing establishment in this 



* Silkworm eggs can be obtained from the Kioto Agricultural School, 

 Kioto, Japan, or from the Nishigahara Agricultural Experimental Station, 

 Silk Culture Dep't, Tokio, Japan, or from Mr. S. I. Kuwana, Buzen, Kiu- 

 shiu, Japan. 



