4 THE AMERICAN MONTHLY (January, 
No. 2. These elements are, without question, most frequently encountered 
in the blood of malarial patients. Form is spherical, but under certain 
conditions may exhibit amceboid movements; dimensions vary from ry in 
diameter to ro or 11. Contour may be either single or double. Seem to be 
made up of a transparent hyaline mass, enclosing black or deep red pigment 
granules, in number from one or two to many disposed ina circle, or without 
order. The spherical bodies are free in the serum, or attached to the red 
corpuscles ; sometimes but a single body, sometimes several, are attached to 
one corpuscle ; sometimes the body fills the corpuscle, which is only recog- 
nized as a zone of pale yellow color surrounding the parasite. Sometimes 
red corpuscles are seen which contain very minute clear spots; it is probable 
that these are produced by the spherical bodies just born, and which do not 
yet contain pigment. The existence of these bodies (No. 2) in the blood, 
independently of the red corpuscles, shows that they have a proper existence. 
The bodies do not exist in the corpuscle, but attached to it and nourished by it. 
This view of Laveran’s as to the position of the body is not shared by 
Marchiafava or Celli, and is not to be regarded as definitely settled. ; 
Laveran further says, that when one examines one of these bodies at a 
temperature of 31°-35° C., it undergoes changes of form, proceeding slowly 
after the manner of an amoeba, and further is observed to divide into several 
portions, which latter is believed by Marchiafava and Celli to represent its 
mode of reproduction. In some cases the close examination of the margin 
of the hyaline body shows the filaments in active motion, which impart to the 
neighboring blood corpuscles rapid and varied movements. These appear 
to represent the adult stage of the microbe. The filaments are at least three 
or four times as long as the microbe, but so transparent as to elude observa- 
tion when at rest, and further, are present only in a certain developmental 
stage of the microbe. They are very active and varied in their movements, 
and may continue so for two or three hours, or cease in a much less time. 
The nature of these filaments as flagelliform pseudopodia is discussed, 
and the question is left open; but there is no doubt that they may entirely 
sever connection with the spherical body to which they were attached, and 
swim about freely among the corpuscles in the plasma. 
No. 3. Laveran describes a third form of body which he regards as a caday- 
eric form of the parasite. This body is a hyaline mass enclosing pigment 
granules variously disposed. That they are cadaveric forms of Nos. 1 and 2 
is shown by the fact that slide at first containing only No. 1 and No. 2 will, 
after standing 24-48 hours, contain No. 3 in large numbers. Further, in 
bodies of individuals dead from malarial fever, No. 1 and No. 2 rapidly take 
the aspect of No. 3, and it is in this condition that they are found in large 
numbers as the hyaline concretions observed in sections in the blood-yessels 
of brain, liver, and notably the spleen, and described by Frerichs. 
The parasite of Laveran he at first called Osczllaréa malarve@, because the 
name implies a recognition of the parasite as vegetable in nature, while the 
discoverer regards it rather as animal. He considers it one of Harckel’s 
protista. Marchiafava and Celli in their latest paper term it Plasmodium 
malarte. 
Having set forth largely in Laveran’s own words the researches he made, 
the writer then proceeds with his exposition of the position which he con- 
siders most consistent with the present state of our knowledge. 
The etiological relation of this parasite to the malarial disease can hardly 
be questioned if additional researches fall into agreement with those thus far 
reported. The idea that a parasite of this kind, which attacks directly the 
blood corpuscles, and is found in fatal cases in vast numbers in or (according 
to Laveran) attached to the essential histological element of the blood, is to 
