The Structure of the Flower of Fagaceae, and its 
Bearing on the Affinities of the Group. 
BY 
E. M. BERRIDGE, B.Sc., F.L.S. 
With nine Figures in the Text. 
O F the families usually classed together under the term Amentiferae, 
the Fagaceae has received less thorough investigation at the hands of 
botanists than almost any other division of this great group. The chala- 
zogamic forms have naturally attracted attention, and those with very 
simple flowers have been carefully examined, in the hope that they would 
reveal primitive characters. Y et the possibility remains that the Amentiferae, 
or at all events certain families among them, are not primitive, but reduced 
forms of some other angiospermic alliance ; if this be the case the Fagaceae, 
including Fagus , Castanea , Castanopsis , and Quercus , would be just the 
division most likely to indicate such an affinity, possessing as they do more 
complete flowers than the rest of the group. 
The opposite view, that the Amentiferae are directly derived from 
certain gymnospermous families, was held by Eichler (8), and was also 
brought forward prominently by Treub (23) after the discovery of chalazo- 
gamy. Engler (9), accepting Treub’s view, and considering this character 
peculiar to Casuarina , placed this genus in a separate group, the Verti- 
cillatae, a connecting link between the Angiosperms and Gymnosperms, 
where it still remains isolated in his system, although more recent work 
has shown that Casuarina differs in no essential manner from other Amenti- 
ferae (4, 10), and that chalazogamy prevails among the Coryleae, Betuleae, 
and Juglandaceae 1 (3, 17, 18). 
Nawaschin, in his elaborate study of the Birch and Alder, suggests the 
derivation of the Betuleae from the Coniferae, and of the Casuarineae from 
the Gnetales, and arrives at the conclusion that the placentae and ovules 
arise from the organic axis of the flower independently of the carpels, 
a view supported by Nicoloff (19) on anatomical grounds. Wettstein, in 
1 For a concise discussion of the systematic position of Casuarina see Moss, C. E. : Modern 
Systems of Classification. New Phyt., vol. xi, p. 209, 1912. 
[Annals of Botany, Vol. XXVIII. No. CXI. July, 1914.] 
Mm2 
