INTERCELLULAR GREGARINA POLYMORPH A 



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anterior end foremost as in ordinary cases, and produced the proto- 

 merite at the posterior end ; and (r) the sporozoite may have entered 

 the epithelium with its anterior end foremost and developed the proto- 

 merite at that end but has made a turn so as to reverse the direction 

 of the body-ends. The first assumption is scarcely admissible, since it 

 stands against our previous knowledge regarding the sporozoites or 

 merozoites of gregarines, coccidians, malarial plasmodia, etc., in all 

 which cases the entrance into host cell is effected by the rostral end 

 directed foremost. The second assumption is improbable, since it 

 stands totally opposed to what experience we have on the matter. 

 The third, it seems to me, affords a most satisfactory explanation. 

 From my observations there seems to exist no difficulty on the way 

 in assuming that a sporozoite, still very small and contained well 

 within the body of a single cell, is capable of making a turn-round in 

 the course of its movement. I presume the sporozoite, on its entrance 

 into an epithelial cell, continue moving on a greater or less distance 

 towards the cell-nucleus ; then it turns round, whereby the anterior 

 end, with which it first penetrated into the cell, is now directed towards 

 the free border of the epithelium. With growth of the animal, the 

 body elongates and eventually produces the protomerite at the anterior 

 end. At the same time it gradually encroaches upon the neighbouring 

 cells. A similar case was observed and reported by LÉGER and 

 DUBOSCQ 1 in StcnopJiora acitlcata, in which species, however, the 

 turning-round seems to occur but very rarely and consequently was 

 regarded by them as an abnormal phenomenon. 



Later the intracellular gregarines escape into the intestinal lumen. 

 In the intestinal canal, I have often noticed free gregarines with their 

 posterior end close to the surface of the epithelium and surrounded by 

 some mucilagenous debris of what seemed to be disorganized host-cells. 

 It has generally been believed that intracellular gregarines become free 

 by breaking through the wall of the host, first projecting the rapidly 



I) Loc cit. 



