EVOLUTIONARY STATUS OF POLYCOTYLEDONY 
ber of cases that were observed, the conclusion that the cotyledons undergo 
a fusion in Larix europaea, while justified, is by no means so well established 
as is a similar conclusion in the case of Picea. 
Table 11. The distribution of the cotyledons and cotyledon primordia in Larix europaea 
Cotyledons or Primordia, Number 
Lot B, 6 Embryos, 
Frequency 
Lot C, ID Embryos, 
Frequency 
Lot D, 34 Embryos, 
Frequency 
5 
I 
3 
II 
6 
2 
7 
20 
7 
3 
0 
3 
Total primordia or cotyledons 
38 
6.33 d= .49 
.74 
57 
5-70 =t .31 
.46 
196 
5.76 ± .39 
•59 
Cedrus is another genus which was found to show fusing cotyledons. 
Through the kindness of Dr. E. J. Kraus, material of Cedrus Libani was sent 
to Texas from one of the trees growing on the Agricultural College grounds 
at CorvaUis, Oregon. The cones were dissected (July 26, 191 8) and were 
Cedrus Libani. Fig. ii, an ordinary embryo without fusing primordia, or before any 
fusions may be seen. Figs. 12, 13, and 15 show stages in the fusion of two cotyledon pri- 
mordia. Fig. 14 has a broad cotyledon which has no doubt resulted from a fusion of two 
primordia. Fig. 16 shows three primordia fusing. Figs. 17 and 18 show reduction of 
cotyledon number when primordia become aborted. X 32. 
