462 
where the phenomena of sex are discernible, in that the dimorphic 
products into which the nuclear apparatus of the latent forms 
separate remain contained within the same animal during its 
successive fissiparous generation. With the exception of this 
difference, however, the phenomena observed are certainly com 
parable to the production of sexual gametes and their conjugation 
In the forms with which we have been hitherto familiar, the retention 
of the nuclear apparatus related to both sexes in one cell, may thus 
be nothing more or less than a morphological curiosity, and in no way 
necessarily suggests that the process in the trypanosomes we have 
been considering is fundamentally different from an ordinary sexual 
differentiation.* 
Assuming the phenomena with which we have just been concerned 
to be of the nature of a sexual process, still another view could 
e with regard to them. It may be suggested that the 
metamorphoses connected with the appearance of the black line .s an 
1 . on P ;lrt trypanosomes to become sexually 
ifferentiated, but this attempt is not completed, the cells reverting 
to their primary condition, in whtch case the process could be 
regarded as an example of a special form of parthenogenesis. I» 
lation to the above suggestion, it should be noted that, at the time 
of he formation of the black line, the whole of the extra-nuclear 
lo«Z° 7 ^ DOt reunite With the nucleus ' but only 0* 
“ of the extra-nuclear centrosome does so. One moiety of Ik 
portions yI C T tr0 0 50me iS detadled from the °*er. and one of to 
forming £ tr^ano ^ ** ^ 
fronT^ 1 mTrat Ft ^ Separat '° n of an extra-nuclear centrosome 
mtra-nuclear ce t Centr ° S ° me throu g h *e division of an original 
cycle, the nucleus enTeTagam '^ ^ B "‘ 3t ™ d ° f * 
centrosome, yet it only doe , connec Oon with the extra-nuclear 
On the other hi it may £ T* * 3 ^ ^ ^ 
---- ^ that the extra-nuclear centrosome 
nucleu 1101 ^ ^ entr o°oni e Glides”and"?, i* 1 ”*!®™ reduction ir > this process. The 
of the' 8 ’ Bot h nucleus and extra-nuclear ^ & f of this bod - v passes out of the 
it re nnt Ceed [ ng Missions. Afterwards entrosorne then divide in the production 
hat dnr CS V th the Helens, andThe rest of «* tra -" ucIe ar centrosome or a part ot 
totii&n; e J ,li «tion a centrosome is °/t^ e K Ce11 b ° d * disa PP ears - b is kn0 "T 
extent the process of fertilization issiinila 0 't^th' 0 th<? eIement: 
