262-263. Second spermatocyte, daughter plates of the two classes.

Plate XV.

Aphrophora quadrangularis.

Figs. 264-265. Second spermatocyte, telophase, showing chromatin nucleolus (n) and the products of division of the odd chromosome (x).

266. A spermatid containing the chromatin nucleolus (n).

267-268. Spermatids containing both the chromatin nucleolus (n) and the odd chromosome (x), a the acrosome.

269. Equatorial plate from a somatic cell of a male larva, 23 chromosomes.

270. Equatorial plate of an oögonium, 24 chromosomes.