A NOTE ON THE INFLORESCENCE AND 
FLOWER OF GNETUM 1 
By H. H. W. PEARSON 
Most botanists who have studied any member of the Gnetales will agree 
that the morphology of the flower is “ none too clear . 2 ” The least obscure of 
the forms of flower found in the group is the male flower of Welwitschia, 
though even here there is much difference of opinion as to the interpreta- 
tion of structural details 3 . In spite of these, this flower is generally 
regarded as a reduced “ Proanthostrobilus ” and is considered to be the 
nearest existing representative of the primitive flower of the group 4 . The 
female flower in each of the three genera is derived from it by the abortion 
of the stamens and by the introduction of changes in the floral envelopes 
which have been the subject of much discussion. It has also given rise to 
the male flowers of Ephedra and Gnetum 5 by the complete abortion of the 
ovule, the abortion or more or less complete fusion of the staminal filaments 
and a measure of reduction in the floral envelopes. These views may 
be perfectly correct, but no one denies that they rest upon very meagre 
evidence. They cannot at present be strongly insisted upon without some 
risk of forcing wrong interpretations and false homologies. 
If the three genera were closely related this risk would be small. Their 
relationships are probably as obscure now as they have been at any time 
within the last decade and proof that they are of near affinity is lacking. 
According to a recent authority 6 the common characters which unite them in 
a single group are “ the compound strobili (both staminate and ovulate) 
resembling inflorescences in which the simple and axillary strobili resemble 
flowers, the conspicuous micropylar tube, the opposite leaves, the dicotyle- 
donous embryo, the true vessels and the absence of resin-canals.” On the 
1 Percy Sladen Memorial Expeditions in South-West Africa, Report, No. 75 (in part). 
2 Scott, 1909, ii. p. 538. 
3 Lignier and Tison, 1912, pp. 58-90. 
4 But see Von Wettstein, 1907, p. 28. 
0 Hooker, 1863, p. 21. Arber and Parkin, 1908, p. 502, Fig. 3, iv, v. 
G Coulter and Chamberlain, 1910, p. 363. 
