5i6 



A H(2matozoon m Human Blood. 



[part III. 



like a ribbon (Fig. 33, 1) — a condition which I had already observed and figured two 

 and a half years ago without knowing what it was. Precisely similar phenomena were 

 observed to occur at the opposite terminal extremity (Fig. 33, 2). 



It was, however, only after the lapse of fully five hours' careful watching, the 

 activity of the Hsematozoon having considerably subsided, that the real nature of what 



appeared to be the rapid protrusion and 

 retraction of the delicate membrane at the 

 oral and caudal terminations were discovered. 

 An unusually long tail was seen to be trail- 

 ing after the " body " of the Filaria for 

 several seconds, and whilst thus being 

 dragged, fortunately it remained exactly 

 in focus, when suddenly the ribbon-like 

 folds were straightened by the darting of 

 the pointed extremity of the worm into the 

 very tip of this hyaline filament (Fig. 33, 2). 

 Scarcely had this taken place than the tail 

 was again retracted and the ribbon-like ap- 

 pendage became evident once more ; where- 

 upon the ribbon-like filament at the other 

 extremity was suddenly straightened in a 

 similar manner and the "head" rapidly 

 projected into the very tip. 



It may be observed that, in the specimen 

 marked 1 in the thirty-second woodcut (page 

 514), no indication of its being enclosed in a 

 capsule is evident. This is frequently the 

 appearance presented by specimens mounted 

 under a fixed covering glass, especially 

 where, as is usually the case, the field is 

 crowded with granular or molecular matter, 

 which so encroach upon the preparation, 

 that the delicate filament formed by the 

 collapsed tube can rarely be distinguished 

 under such circumstances. This tubular 

 envelope is, however, invariably present, and may always be demonstrated when the 

 field is cleared of debris and slight motion communicated to the specimen so as to 

 disengage the free end of the tube, should it be folded back upon the body of the 

 worm, as it very frequently is ; or should the Filaria have been so distended at death 

 as to occupy the entire ^ube, the addition of a fluid differing in density from that in 



Fig. 33. — Various Appearances presented by a single 

 Hsematozoon, as observed under a i" immersion 

 object-glass, x 600. 



