110 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



The second paper of the evening, by Mr. Knab, in reply to Dr. 

 Lutz, was read by Dr. Dyar. 



THE CONTENTIONS REGARDING "FOREST MALARIA." 



BY FREDERICK KNAB, Bureau of Entomology, 



Dr. Lutz's protest against my remarks on malaria transmission by 

 Anopheles bohviensis Th.( = A. lutzii Th.) is interesting and stimu- 

 lating. It seems almost superfluous to say that I have the greatest 

 admiration for the work of Dr. Lutz as I am sure have all who have 

 become acquainted with it. Personally I have derived much in- 

 spiration from the writings of Dr. Lutz and to discredit him was far 

 from my intention. The criticism to which he objects resulted 

 naturally through the defense of an idea which I still believe is 

 correct in principle. The question is a zoological one rather than 

 a medical one, the pathogenic character of the parasite being merely 

 an incident and th fact that Dr. Lutz is a skilled naturalist as well 

 as a physician leads me to hope for points of contact. I must re- 

 iterate, for the benefit of careless readers, that my remarks were, 

 from the beginning, intended to cover only blood-parasites having 

 life-cycles in alternate hosts and involving a blood-sucking insect. 

 It may be here appropriately pointed out that a train of thought 

 very similar to my own led Grassi to his great discovery, which 

 was not, as generally formulated, that Anopheles transmits malaria, 

 but that definite species of Anopheles do so. He conceived the 

 idea that the transmitting blood-sucking insect and the disease 

 must show the same distribution, and this corresponds very closely 

 to what I have formulated. There is, therefore, really nothing new 

 or startling in my contentions. What I -do claim, however is that 

 this aspect should not be neglected by investigators. 



I have again carefully read Dr. Lutz's famous paper and also 

 his present communication. From these it would appear that in 

 the question under dispute, which involves the principle formulated 

 by me, we agree on every point but one, namely the question of the 

 insect host in the malaria epidemic under discussion. I am glad 

 to admit that offering an explanation of conditions at such a dis- 

 tance, and concerning which I had no accurate information, was 

 rash ; but it was only a suggestion and is now withdrawn in the face 

 of the facts brought forward by Dr. Lutz. We find ourselves on 

 common ground in believing that the malarial outbreak observed 

 among a large gang of workmen encamped in a previously unin- 

 habited forest was not endemic there, but was brought into the 

 locality by such of the workmen as already harbored the malarial 

 parasites, and that it was transmitted from man to man by a spe- 



