THE H.EMOFLAGELLATES. 253 



the tertiau parasite (Plasmodium vivax), both the sporo- 

 zoites and mei^ozoites evinciug in their construction charac- 

 teristic Trypanosome features.^ He further considers, aud 

 hopes later to completely demonstrate, that this malarial 

 parasite agrees with Trypanosoma (" Ha) m amoeba") 

 ziemanni in other fundamental respects, as follows: — (a) 

 That the ookinetes of Plasmodium are really formed of a 

 compact coil : and (/') that the '' sporozoites " are not all of the 

 same character, but that indifferent and female ones can be 

 distinguished ; those corresponding to the male forms, how- 

 ever, perish prematurely while still in the ookinete of that 

 type. Moreover, while the indifferent sporozoites are typical, 

 actively-motile Trypanosomes, the female ones no longer 

 appear able to assume the trypauiform condition, but remain 

 gregariniform. 



Schaudinn concludes his remarkable work with an appendix 

 in which he brings forward certain facts noticed by Kossel 

 and Weber, which led these investigators to consider that there 

 is a similar close relationship between Piroplasma and the 

 Haemoflagellates. With this view fSchaudinn, who has exa- 

 mined the preparations, expresses himself in complete agree- 

 ment ; and (it may be here mentioned) it has recently received 

 strong confirmation from the work of Rogers, on anew human 

 parasite, Piroplasma donovani.^ So long ago as 1900, 

 Weber observed in preparations ^ of the blood of a cow suffer- 

 ing from h^emoglobinuria, besides the typical Texas-fever 

 parasites (P. bigeminum), Trypanosome-like forms, much 

 smaller than those of Surra (Nagana) . These parasites showed 

 the general characteristics (shape, nuclear dimorphism, etc.) 



^ In this connection the writer would call attention to the markedly 

 spirochsetiform nature of the sporozoites of Haemogregarina stepanovi, 

 as described by Siegel (105) in Placobdella. 



' A full resume of present knowledge relating to this remarkable para- 

 site is given in the next section. 



^ It may be noted that the blood was drawn towards evening, aud the 

 animal was confined in a stall into which scarcely any light came. Cf. the 

 time when " Halteridium " parasites leave the blood-corpuscles and 

 become free in the blood, as Trypanomorpha. 



