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DESCRIPTION OF PLATES

[The figures were all drawn with Zeiss oil-immersion 2 mm., oc. 12, and have been reduced one-third, giving a magnification of 1,000 diameters.]

PLATE VIII.

_Trirhabda virgata_ (_Family Chrysomelidae_).

FIG. 1. Equatorial plate from somatic tissues of a male pupa, 27 large chromosomes, 1 small one.

2. Equatorial plate from an egg follicle, 28 large chromosomes.

3. Equatorial plate of spermatogonium, 27 large chromosomes, 1 small one.

4. First spermatocyte, synizesis stage.

5. First spermatocyte, early spireme stage, showing unequal pair of chromosomes.

6-7. First spermatocyte, later growth stages.