289 
med by a secondary growth of the tissue of the walls, 
which becomes lignified. 
The nucellus is concrescent for its greater part with 
the inner integument and ends in a sharp nucellar beak 
pointing in the cavity formed by the inner integument. 
The vascular supply is composed of three systems one in 
each of the envelops. For Gnetum Gnemon it is described 
by Berridge (20) and for the Gnetaceae in general by 
Worsdell (178). 
Each of the 12—14 bundles entering the base of the 
female flower, at the level of insertion of the perianth 
give off two traces in this covering and then continue 
their way to supply the two integuments. All these bundles 
are well developed and branch often, running in the 
perianth and outer integument to the top, and in the 
inner one till reaching the level of separation of this and 
the nucellus, But also one or more can be traced in the 
base of the free part of the integument !). 
There has been a good deal of discussion as to the 
three coverings; they have been considered as three in- 
teguments (Strasburger, 147), as a perianth and two 
integuments (Beccari, 12) and as two perianths and one 
integument (Lotsy, 92). In the discussion I shall say more 
about this. 
1) Above the level at which the branches in the perianth are given 
off, a curious complex of vascular tissue is to be seen. It has been 
supposed bij Miss Berridge (20) that these tracheids are ,the vestiges 
of a vascular supply of some whorl of organs, which was situated 
between the outermost covering and the outer integument of the ovule” 
(p. 990). It ,may indicate that the ovule was primitively surrounded by 
a whorl of male flowers. If this were the case the female inflorescence 
of Gnetum would have been originally compound and bisexual and from 
such a form the existing male inflorescence can easily be derived.” (p. 992). 
