62 MOSQUITOES 



authenticated— the fact that the patient suffered from ma- 

 laria, or that his mahiria was caused by the earth carried 

 past in buckets ? I can understand the first being certi- 

 fied to by a doctor, but scarcely the second. How did the 

 doctor prove that the fever was produced by the earth in 

 the buckets ? It seems to me that the only way in which 

 he could have done so in a trustworthy and scientific 

 manner would have been to infect a second person by 

 having- the buckets carried past a second time. I doubt 

 whether such instances— and we see hundreds of them in 

 the press — will bear close examination." 



It has been claimed by Italian observers and others, 

 that there is a very exact coincidence between the geo- 

 grai^hic distribution of malaria and Anopheles mosqui- 

 toes. Bearing on this point, the conclusions reached by 

 Nuttall, Cobbett, and 8trangeways-Pigg, in their studies 

 in relation to malaria (Journal of Hygiene, vol. i., No. 1, 

 January, 1901), are very imi^ortant. They are as fol- 

 lows : 



1. The disappearance of ague from Great Britain does 

 not depend upon the extinction of mosquitoes capable of 

 harboring the j^arasites of malaria. 



2. Three species of Anopheles {A. macui'q>ennis, A. 

 hifu7xatus, A. 7iignpes) are to be found in Great Britain in 

 all districts which were formerly malarious, but also in 

 places concerning which there is no record of the former 

 prevalence of ague. 



3. The Anopheles to-day are most numerous in low- 

 lying land containing many ditches, ponds, and slowly 

 flowing water, suitable for their habitat, and correspond- 



