632 POPULAR SCIENCE MONTHLY. 



been made during the chill, and the blood has not been drawn 

 directly from the spleen ; these observations are therefore to be 

 considered as incomplete, and, if opportunity offers, will be sup- 

 plemented by more extended microscopical researches." 



Notwithstanding this adverse criticism, based upon an experi- 

 mental research made for the purpose of confirming the alleged 

 discovery, if it should prove to have a scientific foundation, the 

 Bacillus malaricB was pretty generally regarded by physicians in 

 this country and in England as being the veritable cause of 

 malarial fevers, and for several years it was frequently mentioned 

 in medical journals and even in standard text-books of medicine 

 as one of the demonstrated disease germs. But truth is mighty, 

 and in the end must prevail. To-day no one speaks of the Bacil- 

 lus malaricB of Klebs and Tommasi-Crudeli except to refer to it as 

 one of the pseudo- discoveries, which for a time passed current, 

 like a counterfeit coin, but which was detected and thrown aside 

 when subjected to approved scientific tests. 



The first confirmation in this country of Laveran's discovery 

 of amoeboid parasites in the blood of malarial-fever cases was 

 made by the present writer in the pathological laboratory of the 

 Johns Hopkins Hospital in March, 1886. In May, 1885, I had vis- 

 ited Rome as a delegate to the International Sanitary Conference 

 convened in that city under the auspices of the Italian Govern- 

 ment, and while there I visited the Santo Spirito Hospital for the 

 purpose of witnessing a demonstration, by Drs. Marchiafava and 

 Celli, of that city, of the presence of the Plasmodium malaricB in 

 the blood of persons suffering from intermittent fever. Blood 

 was drawn from the finger during the febrile attack and from 

 individuals to whom quinine had not been administered. The 

 demonstration was entirely satisfactory, and no doubt was left in 

 my mind that I saw living parasitic micro-organisms in the inte- 

 rior of red blood-corpuscles obtained from the circulation of ma- 

 larial-fever patients. The motions were quite slow, and were 

 manifested by a gradual change of outline rather than by visible 

 movement. After a period of amoeboid activity of greater or less 

 duration, the body again assumed an oval or spherical form and 

 remained quiescent for a time. While in this form it was easily 

 recognized, as the spherical shape caused the light passing through 

 it to be refracted and gave the impression of a body having a dark 

 contour and a central vacuole ; but when it was flattened out and 

 undergoing amoeboid changes in form, it was necessary to focus 

 very carefully and to have a good illumination in order to see it. 

 The objective used was a Zeiss's one-twelfth-inch homogeneous 

 oil immersion. 



The changes in form which a single plasmodium, included in 

 a red blood-corpuscle, was observed by Marchiafava and Celli to 



