CHROMOSOMES OF TIGER BEETLES 461 
tively abundant.. The active cells show little indication of 
rhythm of cell activity. 
The somatic resting cells (fig. 74) are much smaller than the 
germ cells. ‘They usually possess two irregular feathery nucleoli. 
The chromatin material is scattered somewhat uniformly 
throughout the nucleus with here and there slight feathery 
aggregations of fibrillar material. The nuclear wall is very 
conspicuous, while the cell wall is somewhat less apparent. The 
entire cell, in case of the ovarian follicles, is rectangular and 
flattened, caused by the normal growth of the ovary. The 
prophase stage is inaugurated in the usual way by the gradual 
accumulation of chromatin material at various points in the 
nucleus and by a further transformation of these aggregations 
into irregularly shaped chromosomes. The formation of the 
prophase somatic chromosomes differs from that of the germ 
cells, especially in the testis, in that the chromatin aggregations 
are formed indiscriminately throughout the nucleus rather than 
in contact with or near the nuclear membrane. The somatic 
cells are so small that a satisfactory study of the prophase chro- 
mosomes is impossible. 
Although the metaphase chromosomes were very difficult to 
study on account of the crowded and flattened condition of the 
cells, a number of plates were found in which the theoretical 
number, twenty-four, could be definitely established (figs. 76). 
The somatic chromosomes possess, in general, the characteristics 
of those of the germ cells, but show much greater variations in 
size, shape, and general arrangement. This is largely due to 
the crowded condition of the growing ovarian tissue. Many 
instances were noted in which the lateral pressure had been 
sufficiently great to force the metaphase plates into an extremely 
elongated form. Regardless of the variation in size and shape, 
a number of pairs of somatic chromosomes can be definitely 
determined. This observation indicates that the chromosomes 
of the somatic and germ cells possess the same general character- 
istics and that the somatic number in the female is the same as 
the oogonial number (figs. 83 to 86). The anaphase condition 
is characterized by a very early fusion of the chromosomes 
