304 T. H. Morgan 
Equatorial plates of the second division are shown in Fig. 
XXII, 4-D. Here again the four chromosomes are seen. The 
lagging chromosome is now, proportionately to the other chromo- 
somes, much larger. In two cases (Fig. XXII, £, F), the rudi- 
mentary spermatocytes are also shown, and a section (Fig. XXII, 
G,) through a follicle containing the second spermatocyte shows 
how conspicuous these rudimntary cells are at this time. In fact 
(o) (=) he ww é 
G 
A B 
| a ee 
@e 
E F i 
oy | - 
K 
/ J 
Fig. XXIII Chaetophorus viminalis: 4, spermatogonial equatorial plate; B, division of same; C-H, 
equatorial plates of first spermatocytes; J, division of first spermatocyte; }. K, synapsis of chromo- 
somes of egg. 
they form one of the most conspicuous and easily seen features of 
such cysts. 
Another species, Chaitophorus viminalis, produces sexual 
forms in the late summer. It is not favorable for study since the 
chromosomes are numerous, crowded, and one, or more, irregular 
