Embryo of Cephalotaxus drupacea. 1 7 
study I am inclined to believe that these cap-cells originate from a sub- 
division of the first tier at the tip of the pro-embryo. 
My observations on the development of the embryo proper confirm 
Strasburger’s (’ 79 ) account of the embryo of Cephalotaxus Fortunei . As 
shown in Fig. 40 there are four distinct regions to be distinguished. The 
first is the penetrating cap which soon becomes thrown off, the second is 
the embryo itself, the third suspensors, and the fourth the rosette. Unlike 
most Conifers, the cells of the second tier, which constitute the embryo 
proper, divide very rapidly and become very numerous. There may be as 
many as sixteen or thirty-two cells formed before there is any perceptible 
elongation of the suspensors. This early merismatic activity of the embryo 
may explain the necessity for the development of the terminal cells into 
a penetrating cap. This explanation finds support in the fact that the 
cap-cells are thrown off very soon after the suspensors are developed. 
The cap-cells are in two layers. The first consists of five or six cells not 
much larger than the embryo-cells, while the second consists of a very large 
terminal cell, very much elongated and tapering to a point. Very soon 
after the suspensors have reached the length shown in Fig. 40 the cap-cells 
are discarded. The stages shown in Figs. 42 and 43 are soon after the 
cap-cells have been thrown off. 
The suspensors now elongate very rapidly and carry the embryo down 
into the endosperm. The elongation of the suspensors is at first in a 
straight line, but as growth proceeds they become more or less twisted or 
curved. This curvature gradually becomes more marked until a distinct 
winding and twisting form is assumed. As shown in Fig. 43 the suspensors 
become many times the length of the archegonium, and on account of their 
winding growth it is quite impossible to trace them back to their point of 
origin from a single section. 
At an early stage during the elongation of the suspensors there 
appeared to be an occasional budding from the main group of embryo- 
cells and the formation of small secondary embryos. These however were 
not frequently found. As a rule there is but one embryo formed from 
a single archegonium. The small secondary embryos when they appear do 
not develop very far. In one case one of these smaller embryos was 
observed growing towards the neck end of the archegonium, quite in the 
opposite direction taken by the main embryo. Even when two or three 
main embryos from separate archegonia develop, one of them takes the 
lead and grows much more rapidly than the others. Such conditions are 
shown in Figs. 43 and 44. 
The next period in the development of the embryo is marked by the 
appearance of the embryonal tubes or secondary suspensors and the 
disorganization of the primary suspensors. The tubes or secondary 
suspensors were first observed soon after the stage shown in Fig. 43. The 
C 
