I 2 I 
Danaea simplicifolia , Rudge. 
(i. e. stele of the stem) of course consisting of the leaf-trace- 
bundle of the cotyledon until complications arise through the 
addition of the subsequent leaf-traces. The junction is 
effected by ordinary scalariform tracheids. 
Note.— In No. 15 of the Botanisches Centralblatt for 1896 
(Band LXVI, p. 49), Jonkman has a preliminary communica- 
tion on the embryogeny of Angiopteris and Marattia , the 
special interest of which lies in the fact that the embryos 
were obtained by cultivation. He, so far, does little more 
than confirm previous observations ; the most important 
point, however, being that he finds that the growing-point 
of the embryonic stem consists of a few initials, and that of 
the root of four. This agrees in the main with the results 
of previous observers; but Jonkman is disposed to consider 
these conditions as constant, whereas Prof. Campbell and, 
in the present paper, myself are of the opinion that there 
is a certain amount of inconstancy, and that occasionally, if 
not frequently, the embryonic stem, as also the root, has 
a single apical cell. It is somewhat interesting that Jonkman 
finds in Angiopteris and Marattia a group of four equivalent 
initials in the growing-point of the primary root, a number 
which was found in the young adventitious roots of Danaea 
simplicifolia , although the condition of the primary root was 
not satisfactorily made out in the latter. Prof. Farmer had 
come to the conclusion, with regard to Angiopteris evecta , 
Hoffm., that in the embryonic root there is a single apical 
cell, which has a very transitory existence as such. 
