and Fertilization in the Hemlock Spruce. 607 
nucleus are more fibrous than before, and the nuclear membrane has disappeared, 
though the limit of the nuclear cavity remains the same. 
J ig. 48* ( x 800.) The spindle is now monaxial though not yet distinctly 
bipolar. The chromosomes are homogeneous, and no longer separated into two 
groups. The contents of the cavity remain as shown in Fig. 47. 
Fig. 49. (x 800.) This figure apparently represents a later stage than that 
shown in Fig. 48, but no trace of a spindle could be found, even in very deeply 
stained preparations. It must either be considered as a cross-section in which 
the spindle fibres are, for some reason, not easily observed, or the spindle is 
unusually late in forming. 
Fig- 5 °- ( x 800.) The spindle of the first segmentation at metakinesis. The 
division is typical. No centrosomes are present. 
Fig. 51. ( X 800.) Showing a cross-section of the same. 
Fig. 52. (x 200.) Same as represented in Fig. 50, but showing a section 
through the entire egg. The division is here oblique, while in Fig. 56 it is 
represented as longitudinal, and in Fig. 57 as transverse to the axis of the 
archegonium. 
Fig. 53- ( X 800.) The daughter-chromosomes of the first segmentation ap¬ 
proaching the poles in the form of U’s and V’s. By counting them in several 
preparations at this stage, their number was found to be twenty-four. The fibres 
of the central spindle appear twisted and somewhat thickened at the equator, but 
they soon disappear without the formation of a cell-plate. 
Fig. 54. (x 100.) The young daughter-nuclei resulting from the first seg¬ 
mentation. 
Fig. 55. (x 100.) The same at an older stage with the chromatin in the 
resting condition. The cytoplasm between the nuclei is finely granular. Note the 
remains of the ventral canal-cell at the apex of the egg. 
Fig. 56. ( x 800.) A spindle of the second segmentation at metakinesis. It is 
narrower and more pointed than the first segmentation spindle. The chromatin 
divides in the same manner, and there are no centrosomes present. 
Fig. 57. (x 200.) A fertilized egg containing two nuclei in simultaneous 
division. The stage of division is the same as that shown in Fig. 56. 
Fig. 58. (x 100.) The second segmentation is complete, and the four resulting 
nuclei are equal in size and without separating walls. 
Fig. 59. ( x 100.) The four nuclei are moving to the base of the archegonium. 
Their chromatic contents are delicate and scanty. There is no special collection 
of fibres about the nuclei. The archegonium is cut obliquely so that the position 
and size of the nuclei are not truly represented in the figure. 
Fig. 60. ( x 100.) The four nuclei have reached the base and are arranged 
horizontally in one plane. A dense fibrous substance surrounds them. Some 
distance above the plane of the nuclei is a zone showing a regular reticulum quite 
free from staining contents. Above this zone the normal contents of the egg are 
observed deeply stained. 
