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lobes, may strengthen this view. In the normal strobilus 
of Ephedra we may observe the same thing: generally 
there are two uppermost bracts fused together for the 
greater part and still bearing one ovule each, but often it 
occurs that the latter are fused with their integuments 
and finally it is found that only one ovule, then being 
terminal, remained. 
In Gnetum also, no trace of a megasporophyll can be 
observed but a thick cupule envelops the terminal ovule. 
It is most probable that this outer investment represents 
the two fused upper sporophylls, from which only one 
ovule has developed. 
In Welwitschia we have the same thing, here also a 
conspicuous megasporophyll is absent. But it seems to me 
most acceptable to regard the winged envelopment in 
the female flower as consisting of two fused sporophylls. 
They stand in the median plane and alternate with the 
transverse scales, which are observed in few cases. Also 
Strasburger (147) and Eichler (64) were of the 
opinion that the winged membrane was composed of two 
carpels, but according to them, they should stand in the 
transverse plane. 
On account herewith the megastrobilus of Gnetum and 
that of Welwitschia are compound. The ovules of Ephedra 
and Gnetum are provided with two integuments, whereas 
the gynaecium of Welwitschia in the male as well as 
in the female strobilus consists of a nucellus enveloped by 
one integument. 
Now I have come to the solution of the questions put 
forth in the first chapter, and the first thing to be done 
is to determine, what we may understand by the name 
»integument.” Às the result of my investigation the 
envelopment around the nucellus always seems to consist 
of units. The inner investment of Lagenostoma and 
Sphaerostoma of Taxus, Torreya, Podocarpus and Wel- 
