heterochromosome

The heterochromosome group is blended into a vacuolated sphere in growth stages (figs. 199, 200).

Figure 137 is an exceptional anaphase in which the heterochromosome elements are not mingled with the polar masses of chromatin.

The small heterochromosome divides in the second spindle in advance of the others as seen in figure 150.

Bouquet stage from iron-hæmatoxylin preparations, showing the heterochromosome bivalent (x).

Of the insects considered in this paper Aphis and Termopsis have no "accessory chromosome" or "heterochromosome" of any kind.