[194] Quinine is still almost exclusively the remedy used in the treatment of malaria. It is prepared from the bark of the cinchona tree. This important remedy was introduced into Europe in 1640 from Ecuador by Juan del Vego, physician of the Countess del Cinchon.
[195] The discovery of Laveran is in no way lessened by the fact that one investigator or another (according to Blanchard [Arch. de Paras., vii, 1903, p. 152], P. F. H. Klencke in 1843) had seen, mentioned and depicted malarial parasites. (Neue phys. Abhandl. auf. selbständ. Beob. gegr., Leipzig, 1843, p. 163, fig. 25). In 1847 Meckel had recognized that the dark colour of the organs in persons dead of malaria was due to pigment. Virchow in 1848 stated that this pigment occurred in blood cells. Kelsch in 1875 recognized the frequency of melaniferous leucocytes in the blood of malarial patients. Beauperthuy (1853) noticed that in Guadeloupe there was no malaria at altitudes where there were no “insectes tipulaires,” and suggested that the disease was inoculated by insects.
[196] Grassi, B. (1901), “Die Malaria,” 250 pp., 8 plates. G. Fischer, Jena.
[197] It should be remembered that some authors (Laveran, Argutinsky, Panichi, Serra) argue against the intra-globular position of malarial parasites and state that they only adhere outwardly to the red blood corpuscles. These views have recently been revived by Mary Rowley-Lawson, and she states that the malarial parasite is “extracellular throughout its life-cycle and migrates from red corpuscle to red corpuscle destroying each before it abandons it.” (Journ. Exper. Med., 1914, xix, p. 531.)
[198] The incubation period, that is, the time between infection and the first attack of fever, is ten to fourteen days; with severe infection fewer days (minimum 5 to 6) are needed.
[199] Schizonts ingested about the same time perish in the intestine of the mosquito.
[200] If the microgametocytes are sufficiently mature the formation of microgametes occurs in the blood of man as soon as it is taken from the blood-vessel and has been cooled and diluted. Such a stage is called a Polymitus form, and the process has been called “exflagellation.”
[201] See Schaudinn, F. (1902), Arb. a. d. kaiserl. Gesundheits., xix, pp. 169–250, 3 plates.
[202] The pigment masses (melanin or hæmozoin) are taken up by the leucocytes, particularly the mononuclear ones, and are carried especially to the spleen, and also to the liver and the bone-marrow. From this circumstance arises the well-known pigmentation of the spleen in persons who have suffered from malaria.
[203] Bull. Soc. Path. Exot., vii, p. 385.