354 Kershaw . — The Structure and Development of 
Miss Benson’s 1 work on the Amentiferae showed that this classification 
could not possibly be adopted. Treub was evidently misled by Hofmeister’s 
account in 1858 of the embryology of the Amentiferae, for Miss Benson 
very clearly shows that Be tula , Alnus , Corylus , and Carpinus are also 
Chalazogams. In many other characters also the Amentiferae very closely 
resemble Casuarina. 
There is a considerable amount of sporogenous tissue, which although 
differing in detail from that of Casuarina , is thought by Miss Benson 
to constitute an important point of resemblance ; the pollen-tubes are 
of the branching type, and in many genera enter the nucellus through 
the chalaza. Such characters as the large amount of sporogenous tissue 
in the ovule and the great number of macrospores which develop, may 
be regarded as primitive, and have been considered to support the posi- 
tion assigned to the Amentiferae and Casuarinaceae by Engler in his 
scheme of classification of the Angiosperms. 
The investigations of Nawaschin 2 on Juglans regia , and those of 
Karsten 3 which extended to other members of the Juglandaceae, show 
that chalazogamy prevails also in this family. 
It is interesting to note Nawaschin’s views on chalazogamy. He 
states : c die Chalazogamie stellt eines von den Uebergangsstadien dar bei der 
Umwandlung des intercellularen Wachsthums des Pollenschlauches im 
gymnospermen Fruchtknoten zum freien Wachsthum durch die Frucht- 
knotenhohle der Angiospermen.’ 
A more detailed account of the structure and development of the 
ovule of Juglans regia was given by Nicoloff 4 in 1904, details of which will 
be referred to later. 
As regards the Myricaceae, Treub 5 had already in his paper on 
Casuarina shown that in Myrica Lobbii the course of the pollen-tube was not 
chalazogamous, but that development and fertilization were of the normal 
Angiospermous type. 
As this was based on one species only, it was suggested that an 
investigation of the ovules of other species might prove interesting as 
a further comparison. 
For this purpose Myrica Gale , which grows fairly abundantly round 
some of the Cheshire meres, — particularly Hatchmere in Delamere Forest — 
was chosen. 
I found in this British species, just as Treub found in Myrica Lobbii , that 
1 Benson: Trans. Linnean Soc., London, vol. iii, part io, 1894. 
2 Nawaschin : Ein neues Beispiel der Chalazogamie. Bot. Centr., 1895, 63. 
3 Karsten: Ueber die Entwickelung der weiblichen Bliithen bei einigen Juglandaceen. Flora, 
90. Band, 1902. 
1 Nicoloff: Sur le type floral et le developpement du fruit des Juglandees. Journal de 
Botanique, t. xxviii-xxix. 
6 Treub: loc. cit. 
