114 
JOHN T. BUCHHOLZ 
found to contain embryos in the cotyledon-forming stages. There was 
again a great scarcity of good seeds in the cones, a condition which is due to 
poor pollination and is almost always met with when a species is cultivated 
out of its native region. That this species should show fusing cotyledons 
came as a surprise, because there were found to be from seven to twelve 
cotyledons (average about nine) , and the writer had been expecting to find 
cotyledonary fusions among species with a small number of cotyledons. 
Fig. 19. Larix embryo from lot C showing a very slight inequality in the first appear- 
ance of the primordia. X 32. FiGS, 20-22, embryos of Picea mariana showing a similar 
slight difference in the origin of the cotyledon primordia. Fig. 20 from lot B, Figs. 21 and 
22 from lot C. X 32. Fig. 23, a diagram illustrating the manner in which cotyledon 
primordia frequently appear when unequally developed, suggesting that they are essen- 
tially spiral. 
Fig. 24. Section near the tip of the cotyledons of a fully developed embryo of Pinus 
Laricio, showing a bilateral grouping of the cotyledons. Fig. 25, a similar section taken 
lower down on the same embryo. 
The fusions of the primordia are gradual and so plainly seen that in this case, 
as in Pinus Banksiana, the statistical method is not necessary to convince 
one of what is taking place. Figure 11 shows an ordinary embryo with 
cotyledon primordia surrounding the primordium of the stem tip (shaded), 
and figures 12-16 show a number of typical cases with the fusing cotyledons. 
Out of twenty-five embryos in cotyledon primordia stages, eight such coty- 
ledons were found which showed that fusions were taking place. Figure 16 
shows three primordia that are apparently fusing. 
Cedrus has two methods by which its cotyledons are reduced in number. 
One of these is fusion, and the other is the abortion of primordia as shown 
in figures 17 and 18. Two instances of this kind were found and are here 
figured, but in embryos much older than these this vestige would be over- 
looked, if it could be found at all. 
An interesting fact which can be observed in many pine embryos is the 
tendency to become bilateral. The cotyledons frequently develop in two 
groups, and this is well shown in figure 24 which is drawn from a cross 
section near the tip of the cotyledons of an embryo of Pinus Laricio. As 
shown by figure 25, a section taken lower down on the same embryo, this 
arrangement of the cotyledons in two bilateral groups is noteworthy. It 
