s no
rest stage between the two maturation divisions, but the late anaphase
of the first mitosis passes over quickly into the second spindle.
Figures 54 and 55 are typical equatorial plates of the second division,
one showing the small chromosome (_s_), the other its mate more nearly
spherical than the others (_l_). An anaphase including the small
chromosome is shown in figure 56. As in the species previously described
the spermatozoa are evidently dimorphic.

Female somatic equatorial plates from egg follicles are shown in figures
34 and 35; 22 chromosomes are present and no one is without an equal
mate.

Odontota dorsalis (Family Chrysomelidae).

_Odontota dorsalis_ is a small leaf-beetle found on _Robinia
pseudacacia_. The chromosomes are comparatively few in number, 16 in the
spermatogonia (figs. 58 and 59), and of immense size when one considers
the smallness of the beetle. In some of the spermatogonial cysts many of
the chromosomes are V-shaped as in figure 58, while in others all, with
the exception of the small one, are rod-shaped as in figure 59, which
looks like a hemipteran equatorial plate. The spermatogonial resting
nucleus (fig. 60) contains a large plasmosome (_p_), but no condensed
chromatin. The synizesis and synapsis stages are similar to those in
Chelymorpha (figs. 61 and 62). The spireme stage (figs. 63, 64)
contains, in addition to the pale spireme, a very conspicuous group
consisting of a large plasmosome with a large and a small chromosome
attached to it. In the prophase, before the nuclear membrane has
disappeared, this group is easily distinguished from the other
dumb-bell and ring-shaped bivalents (figs. 65-67). In preparations much
destained (fig. 67) the small chromosome component of the group retains
the stain longer than the larger one. The spindle in prophase (fig. 68)
is much elongated and the 8 chromosomes are often spread out upon it so
as to be easily counted. In the early metaphase the parachute-like
heterochromosome group is always nearer one pole of the spindle (plate
X, figs. 69 and 70). The equatorial plate often shows both the larger
component of the pair and the plasmosome (fig. 71). Figures 72-74 show
the metakinesis of the heterochromosome bivalent. In figure 74 the two
unequal elements are completely separated and the plasmosome has
disappeared. The equatorial plates of the two resulting kinds of second
spermatocytes appear in figures 75 and 76. In the anaphase of the se