CHROMIDIA AND THE BINUCLEARITY HYPOTHESES, 3818 
with its nucleus and Nebenkorper representing a stage inter- 
mediate between the diatom and the A. binucleata con- 
dition. 
These views were all very clearly expressed and are the 
parents of the existing binuclearity hypothesis of Schaudinn 
and his followers. 
Schaudinn’s (96a, 704, etc.) conception of binuclearity was 
chiefly based upon his observations on Acanthocystis and 
Hemoproteus (Trypanosoma) noctue. In the latter we 
see an organism which is actually binucleate, there being a 
TEXT-FIG. 23. 
a. 
Illustrating three different kinds of binuclearity which actually 
exist in three different groups of Protozoa :— 
a,in the Rhizopoda, Amceba binucleata, an organism with 
two exactly similar nuclei (n. w’.). 
b, in the Flagellata, Hemoproteus noctux, which has two 
differentiated nuclei—kinetic (k.n.) and trophic (¢.7.). 
c,in an Infusorian. Here the nuclei are differentiated into a 
somatic (meganucleus, M.) and sexual (micronucleus, 7.). 
The three figures also serve to illustrate the starting points of 
the three binuclearity hypotheses,—namely those of Lauter- 
born, Schaudinn Hartmann and Prowazek, and Goldschmidt 
—respectively. 
second nucleus (kinetonucleus) in addition to the main nucleus 
(trophonucleus). Both nuclei take part in conjugation, and at 
certain periods in the lfe-cycle they may be united into a 
single nucleus (synkaryon). The kinetonucleus (blepharo- 
plast) is specially concerned with the locomotor functions of 
the cell. 
Now it is this second nucleus—the kinetonucleus—which is 
