THE HAEMOFLAGELLATES 



257 



or less to the radial or rosette type of multiplication (I, c), enlarged 

 rounded parasites, with a varying number of nuclei (up to about 10) 

 uniformly arranged near the periphery, having been often noticed. The" 

 details are, however, rather differently described by different workers. 



Our knowledge of any further development undergone by these 

 parasites is limited at present to the Leish man-Donovan bodies, and is 

 due in the first instance to Rogers (94). Rogers cultivated the parasites 



FIG. 39. 



I, Leishmania (Piroplasma)don6vaiti (Lav. and Mesn.). a, typical pear-shaped or oval forms ; 

 b, various stages in binary fission ; c, nuclear division, preparatory to multiple fission ; d, endo- 

 corpuscular forms in red blood-corpuscles (p, pigment grains); e, bacillary form of the parasite 

 in, a corpuscle ; .U, large rnaerophageal cell with many parasites. (After Donovan.) II, Uni- 

 nuclear leucocyte (/.) containing several parasites. (After L. and M.) Ill, /,. (P., Helmsoma) 

 trnpica (Wright). , single individuals ; b, dividing forms, (h'rom Mesnil, mostly after Wright.) 

 IV, L. (P.)donncani in cultures of different ages, a, ordinary forms of varying size ; b, c, stages 

 in multiple division ; e, f, and g, flagellate forms. (After Rogers.) 



in citrated blood, at a lower temperature, and made the astonishing 

 discovery that Flagellate forms were developed from them. This result 

 has since been fully corroborated and further details ascertained by Christo- 

 phers (87), Leishman and Statham (92), and others. Different stages 

 in the process are seen in Fig. 39, IV, d-g ; and Fig. 40. The parasites 

 increase greatly in size and become vacuolated (this is probably due to 

 the artificial medium in which they are). Multiplication by binary fission 

 takes place, and with successive generations the shape of the body alters ; 

 from being pyriform it passes through a fusiform condition, and finally 

 becomes elongated and slender. Meanwhile, in many of these phases, a 



17 



