1897] THE LIFE HISTORY OF SALIX 165 
made no special study of the upper part of embryos older than 
that represented by this figure. The embryo loses its spherical 
or ovoid form, becomes flat across the top, two regions of more 
rapid cell division and growth appear which push the cotyledons 
up above the less active meristem of the main axis, and the 
embryo assumes the characteristic form shown in fig. 66a. 
No account of Salix would be complete without mentioning 
peculiar embryos which depart from the normal course of devel- 
opment and for a time seem to have an apical cell. In one of 
these embryos (fig. 6z) the apical cell is three-sided, and has 
cut off two segments in true pteridophyte fashion. A surface 
view of another is shown in fig. 6g, and a median section of the 
Same embryo is given in fig. 63, while still another peculiar 
embryo is shown in fig. 62. No trace of such apical cells is found 
in embryos older than these. If such embryos mature, it would 
be interesting to discover how the periblem and plerome differ- 
entiate, and what part the suspensor plays in the development. 
TERATOLOGY. 
Salix has been notable always for the frequency and variety of 
its sports. It is now monosporangiate and dicecious, but embry- 
ology gives no evidence that this is due to suppression, suggesting 
rather that it represents a primitive condition. 
A vigorous plant of S. g/aucophylla was found in the spring of 
1895, many of the pistillate catkins of which were three or four 
inches long. A few catkins were entirely staminate, others were 
entirely pistillate, but many were mixed, some of the bracts hav- 
ing two stamens, some having one pistil, others having one pistil 
and one stamen, and still others having one pistil and two sta- 
mens. The pollen and stigmas matured at about the same time. 
Sections of the pistils showed perfectly normal conditions from 
the origin of the macrospore to the mature seed. The plant 
_ behaved the same way the next spring, and buds collected dur- 
ing the past winter showed that the same peculiarities will be 
continued. I have planted seeds to discover whether these char- 
acters can be aumer in that way. 
ES Ie alae eet ao 
