THE MORPHOLOGY AND AFFINITIES OF GNETUM 1 47 
and Tison, 17 and 18). These views seem to include all the possibili- 
ties and it will perhaps be difficult to choose between them until the 
anatomy is studied in a wider range of forms. Nevertheless the con- 
ditions described in the preceding pages have a bearing on the problem 
which should be pointed out. 
In regard to the view that all three envelopes are integuments it is 
only necessary to remark that there is no evidence except their general 
appearance in favor of it. Such a view, moreover, fails to offer any 
explanation of the envelope of the male flower which is evidently of 
the same type. 
The second view, namely that the two inner envelopes are true 
integuments and the outer a perianth or something analogous to it 
is the one most generally held at the present time and most convincing- 
ly stated by Coulter (7) . This author pointed out that those coverings 
of the ripe seed which are derived from the two inner envelopes are 
the same as those derived from the single integument of Gymnosperms : 
an inner fleshy, a middle stony, and an outer fleshy. The inner 
fleshy layer of Gnetum is derived from the inner envelope and the 
other two from the middle envelope. Accordingly Coulter con- 
cluded that the inner envelope of Gnetum represents the inner part 
of the single integument of Gymnosperms and the middle envelope 
represents the remainder of this single integument. In other words 
the single integument of other Gymnosperms has become divided 
into two distinct integuments in Gnetum. Opposed to this view is 
the style-like character of the projecting portion of the inner envelope 
which strongly supports the view that it is really an ovary and not an 
integument. Further, the development and anatomy of this envelope 
in both Ephedra and Welwitschia indicate that it really consists of 
two fused members. 
The third view (that there are two integuments and an ovary) 
is at first sight very attractive particularly when this flower is com- 
pared with that of one of the lower Angiosperms such as Peperomia. 
Figure 16 represents a section of a flower of Peperomia sp., and if it is 
compared with a section of a Gnetum flower it is seen that the re- 
semblance is very striking and that the carpel of Peperomia corres- 
ponds closely to the outer envelope of Gnetum. Moreover the 
development of the flower of Peperomia is almost a repetition of that 
of Gnetum (Johnson, 11). In form and position with respect to the 
remainder of the flower this envelope certainly resembles an ovary as 
