252 
are, however, amongst them, several differences left as to 
some of the details. 
That the arillus surrounding the ovule is nothing else 
but the reduced lamina of the leaf, appears clearly from 
teratologicals found bij Fujii (66): ,, The ovule is partially 
enclosed at the base in a cup-shaped swelling just as in 
the normal ones, and this swelling gradually passes into 
the lamina of the leaf.” But as to the position of the 
sporophylls on the axis of the strobilus, the opinions are 
not settled. Strasburger (147) and also Eichler (61) 
describe the strobilus as being formed by an axis bearing 
a pair of transverse leaves and in some cases a second 
pair of median leaves besides. The latter has given in his 
,Blüthendiagrammen” (61 p. 65) a diagram of such a 
,vier b'üthiges Zweiglein”. In this the ,Blüthen” are de- 
cussate, each consisting of a nucellus, a ,,Blüthenhülle” 
composed of two segments and the fused , Vorblätter” 
(the arillus). It will become evident from my futher dis- 
cussion that this diagram does not agree with the true 
interpretation of the composing organs. 
Von Wettstein (168) agrees also with the decussate 
position as being the most normal one, and has come to 
this, owing to his investigations upon the vascular supply 
in the axis of the strobilus. 
Afterwards the vascular supply has been further exa- 
mined by Seward and Gowan (136), which I have 
repeated. 
Every ordinary leaf contains two collateral vascular 
bundles lying close together in its petiole. Below the 
place of insertion they form a ring in the main branch 
with the bundles of the other leaves. À transverse section 
through the axis of the strobilus shows entirely the same 
behaviour as that of a leaf bearing stalk, each ovule 
receives a double vascular strand. In the normal cases in 
which the strobilus bears two, three or four sessile ovules, 
