320 H. M. WOODCOCK. 



They propose the name Trypanosoma luis^ for the para- 

 sites when in the former condition. 



K. and S. also bring forward observations pointing to the 

 occurrence of sexual forms and conjugation. The wider try- 

 paniform parasites are themselves considered to represent 

 female elements. In the same preparations showing these 

 are also to be found peculiar spirals differing from the ordinary 

 ones in being much longer and relatively wider, and in pos- 

 sessing several '^nuclei" each having a corpuscle in relation 

 with it (fig. 65/.) . By the side of these elongated multinuclear 

 forms may be seen also very fine and minute ones, about 3 fx 

 long {g.). Each is falciform with pointed ends, possesses 

 one " nucleus " and " corpuscle," and appears identical with 

 one of the turns of the compound spiral. These tiny forms 

 correspond to male elements and probably result from the 

 fragmentation ^ of the others. Boths kinds of gamete may 

 undergo longitudinal division, the males thus becoming ex- 

 tremely delicate and diflScult to perceive [cf. T. ziemanni, 

 p. 243]. 



Only in one case were K. and S. able to find stages which 

 resembled the process of conjugation, in a preparation from a 

 large primary ulceration which was commencing to cicati-ise. 

 A male gamete becomes attached to a female gamete by one 

 of its extremities (fig. 65 h.), and the two gradually join to- 

 gether (laterally) and at length fuse completely. The subse- 

 quent development was not followed. The authors think that 

 probably a resting-period ensues in which the parasite may 

 become encysted, and this in turn gives rise to the indifferent 



^ Even if this parasite is ultimately shown to be a true Trypanosoma, 

 and the generic name Spironenia is, in consequence, retired, the specific 

 name must still be pallidum. Pending further investigation, however, it 

 seems best to retain the generic name also, as although probably a Trypano- 

 some, this form may dilTer somewhat from the genus Trypanosoma. 



2 The authors consider that this apparent transverse division is easily 

 derivable from the successive longitudinal fission of the " Spiroeiiaitte," by 

 supposing that the parasites remain all closely attached end-to-end, become 

 somewhat modified (condensed), and ultimately separate into the constituent 

 units. 



