Paludism / by A. Laveran ; translated by J.W. Martin.

  • Laveran, Alphonse, 1845-1922.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Paludism / by A. Laveran ; translated by J.W. Martin. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    take place rather slowly like those of amoebm, are easy to see when the same element is in the centre of the field of the micro- scope, and is drawm say every minute. These spherical bodies are at times free in the serum (k, l, n, o, Fig. 1), at times adherent to the red blood-corpuscles (b, c, d, e, e, g) ; on the same blood-corpuscle sometimes two, three, or four of these bodies are found (n, i). These parasites evidently live at the expense of the blood- corpuscles, which grow pale in proportion as the parasitic elements which adhere to them increase in size; there is a time when the blood-corpuscle is only distinguished by its contour; its charac- teristic colour has disappeared, its transparency is the same as that of the parasite, and soon the corpuscle disappears com- pletely. The red blood-corpuscles attacked by parasites have often a dia- meter considerably larger than that of the normal blood-corpuscle ; the characteristic yellowish colour and their disc-like shape also disappear, the blood-corpuscles becoming, so to speak, dropsical. Are, then, the parasites enclosed in the blood-corpuscles, or are they simply adherent to them ? This question, which after all is secondary, is difficult to answer by direct observation. Our knowledge of the structure and composition of the blood- corpuscles in man makes it difficult for us to understand how these parasites can enter them. The probability is that they simply adhere to the blood-corpuscles by pressing upon them. What makes this supposition more likely to be true is that the parasitic elements are often found in the blood in a free state, and that at all periods of their development. The spherical bodies may be multiplied by means of segmenta- tion or by budding. On examining minutely one of these elements possessing amoeboid movements, it sometimes happens that this body is seen to divide into three or four similar but smaller elements ; these elements separate themselves and become free. Some kinds of sarcoid balls are sometimes formed on the edges. After a variable time, seldom extending over half an hour or three quarters of an hour, the movements of the granules of pigment stop, and the spherical bodies take their cadaveric form ; the contours are more or less irregular, the pigment collects in certain points ; the bodies are still easily distinguished from the melaniferous leucocytes by the absence of a nucleus. Some observers have described a nucleus in the spherical bodies; if it exists (which is not yet proved), this nucleus is