liEPKOUUCTION OP KALriBOliHYNCHUS AliPNlOOL.E. 569 
the dark or female side the chains of pearls lie on the edges 
of convoluted bauds, which have about half the depth of 
those on the male side, showing that in the male gametocyte 
there is much more protoplasm left over after the formation 
of the gametes than in the female. The nuclei also can be 
seen in many cases to be about twice as large on the pale as 
on the dark side (fig. 6). This convinced me that we have 
anisogamy here, the chief thing which led me to this 
conclusion being the difference in size between the nuclei 
of the gametes in the respective gametocytes. But it would 
not have been easy to prove this difference by means of 
sections only, for tlie cysts were cut in all mauner of planes. 
I therefore broke numbers of cysts at random on different 
slides, and was fortunate enough to isolate in this way a few 
female gametes fi-om the “pearl stage” and a number of 
conjugation stages from cysts containing conjugating gametes. 
Unfortunately i did not so isolate a male gamete, but in the 
conjugation stages one could see its shape perfectly well. 
The female gamete is nearly spherical in shape with a 
spherical nucleus, which, as a rule, has darker and more 
concentrated chromatin than that of the male gamete. This 
nucleus has a volume equal to about one fourth of that of the 
whole gamete. 
The male gamete, on the other hand, consists almost 
entirely of an oval, sometimes of a pyriform nucleus, which 
is surrounded by a very thin layer of protoplasm. This 
nucleus is generally about twice as large as tliat of the 
female gamete. The oval nuclei are the more common 
(fjg- ^)- 
While the nucleus of the female gamete is surmounted by 
a wide, low cone, the cone on the male nucleus is high and 
narrow. In both cases tlie centrioles can often be seen to be 
double. 
In the act of conjugation it seems as though the male 
nucleus with its cone forces itself through its own protoplasm, 
which it casts off like a sheath as it enters the female gamete 
(fig. 7, h, c, d, etc.). This is what happens most frequently. 
