632 APPENDIX. 



ordinary rapidity. A flagellum may break off from 

 the main body and move about independently among 

 the corpuscles. While these flagellate bodies appear 

 in both the tertian and quartan fevers they are very 

 much more numerous in the irregular malaria. The 

 significance of the flagellate form is still under discus- 

 sion. By some it has been regarded as a degenerate 

 form. 



In the sestivo-autumnal, quotidian, or pernicious mala- 

 rial fevers there is developed also a very striking body, 

 to which much attention has been paid, viz., the <e cres- 

 cent " of Laveran. In any case of irregular malarial 

 fever which has lasted a week or more these bodies are 

 to be found. They are developed within the red blood- 

 corpuscle, the margin of which may usually be seen on 

 the concave surface of the crescent. The border is very 

 sharply defined, the protoplasm uniform, homogenous, 

 with coarse pigment granules, often in the form of rods, 

 which are collected about the centre. Bodies similar 

 in structure, but differing in form, being ovoid and 

 rounded, are also met with ; and the change of a cres- 

 cent into an ovoid or rounded body can be traced, which, 

 in turn, may in some instances be seen to project flagella 

 or form a flagellated body similar to that derived from 

 the extracorpuscular organisms above referred to. 

 Most authors say that both kinds of flagellate bodies 

 do not develop unless the blood be exposed to the air, 

 but an exposure of one or two minutes gives the best 

 results. It would seem that they do not exist as flagel- 

 late forms in the circulation. (Osier, in Allbutt's Sys- 

 tem of Medicine.) 



Pigmented Leucocytes. Typical pigmented leucocytes 

 are very characteristic signs in malarial blood, and on 



