482 Mr. L. Doncaster. [Jan. 25, 
nuclei, either evenly stained throughout or consisting of a deeply stained 
mass surrounded by a narrow clear space. When the nuclei of the blasto- 
derm are dividing, which they all do simultaneously, they show clearly 
defined, though very small and compact, mitotic spindles; the nuclei of 
the yolk in the same egg show no spindles, and strongly suggest amitotic 
division, for various stages can be found, from nuclei which are simply 
elongated to two or sometimes three nuclei in which the membranes are in 
contact (figs. 19, 20, a, 0). Stages of this apparent amitotic division are 
found in the yolk-nuclei of most eggs in the blastoderm stage, whether the 
blastoderm-nucle1 are undergoing division or not. In advanced blastoderm 
stages below the layer of blastoderm-nuclei there is a belt of protoplasm with 
no yolk, and inside this the yolk fills the centre of the egg, and contains all 
the yolk-nuclei, none being found in the protoplasmic belt. 
In two large series of eggs (each laid by a single female) a number of later 
segmentation stages are represented preceding the formation of the blastoderm. 
Unfortunately, neither of these series contains any egg which shows con- 
clusively whether it is haploid or diploid. Both contain eggs showing bodies 
at the edge which might be remnants of the polar chromosomes, but which 
cannot be identified as such with certainty. In some eggs, but not in all, of 
both series, very large nuclei occur, among which are scattered others of the 
normal size. In late segmentation stages these large nuclei are sometimes 
found in division; the figures are obscure, possibly owing to imperfect 
fixation, but appear to be diploid. Divisions of the smaller nuclei, on the 
other hand, suggest haploid figures, but I have none in which the chromo- 
somes can be counted (fig. 21, a, 6). In other eggs, some of these large nuclei 
are elther undergoing amitotic division or are being formed by fusion of two 
or more smaller nuclei; groups of two, three, or even more nuclei are 
found in close contact, while here and there are large, apparently single 
nuclei as big as the group of smaller ones (figs. 22, 23, 24). In some eggs 
among these are nuclei which are drawn out into processes, or have an 
irregular shape (fig. 25). At this stage the distinction between yolk- and 
blastoderm-nuclei cannot be made, for all are scattered indiscriminately 
through the egg; they are most numerous at the lower end of the egg, 
towards the stalk. In eggs of other series the nuclei are all alike at this 
stage, and show nothing unusual, but that the two series described are not 
entirely exceptional is shown by the occurrence of one or two similar eggs 
among later segmentation stages collected in 1908. That the phenomena are 
due entirely to bad preservation appears improbable. From incomplete 
observations such as these it would be premature to draw definite con- 
clusions, but it may be suggested provisionally that during the later 
