THE SPOROGONY OF THE MALARIA PLASMODIA 95 



pheral blood as they are gone through in the spleen, liver, bone- 

 marrow and cerebral capillaries. The latter, indeed, are frequently 

 crowded with plasmodia undergoing schizogony, thereby explaining 

 the severe cerebral symptoms. The number of small merozoites, 

 arranged spoke-like, average from seven to twelve, rarely more. 



In this type of fever, Laveran's sickles or so-called crescents, are 

 more frequently met with than in other fevers. 



FIG. 38 The " pernicious para- FIG. 39. The crescents (Laverania) of the 



site " in the red blood corpuscles pernicious parasite. (After Mannaberg). 



of man. (After Mannaberg.) 



4. DOUBTFUL SPECIES. 



The independence of the three foregoing species that are distinguished one 

 from the other by their morphological and biological characteristics, has also 

 been proved by the results obtained after inoculation of the blood of malaria 

 patients into healthy persons ; this can even be accomplished with very small 

 quantities. After varying periods those inoculated always acquire malaria 

 which is of the same type as that of the case from which the blood is 

 taken. 



According to Celli, 1 and in opposition to the views of many authors, 

 an actual quotidian fever occurs in summer and autumn, the agent of 

 which is closely related to the Plasmodium of Tropical fever. The quotidian 

 parasite is, however, smaller, has granules of pigment that are scarcely per- 

 ceptible, and completes its cycle of development in the blood in twenty-four 

 hours. Another very rare form has been observed by Celli and Marchiafava 

 in Italy, and by Marchoux in the Tropics ; it develops in less than twenty- 

 four hours, without transforming the haemoglobin into melanin. The inde- 

 pendence of these two forms is questionable ; they are mostly regarded as 

 varieties of the plasmodia of tropical fever. 2 



5. THE SPOROGONY OF THE MALARIA PLASMODIA. 



Forms have already been mentioned in the above description 

 of the malaria parasites of man that are incidentally met with, 

 besides the stages of schizogony ; these are the so-called SPHERES 

 and CRESCENTS, or SICKLES (fig. 39). They were found in blood just 



1 Celli, A., Die Malaria nach den neuesten Forsch., translated by Kerschbaumer, 

 Berlin, Vienna, 1900 (Celli, A., La malaria sec. le nuove ricerche., 2nd edition, Rome, 1900). 



' 2 The same may hold good for Laverania limnhtmica, the malaria parasite of the 

 Cubans (Coronado, O. V., in Crdnica med quir. de la Habana, 1897, No - 6 ' and c - / 

 B., P. u. /., 1897, xxii., p. 558). 



