BOOK-NOTES, NEWS, ETC. 81 
nected to the cell-walls by delicate strands some of which are clearly 
re hyphe. These masses very closely resemble those described 
y Shibata in the mycorhiza of orchids. Small bodies, similar to 
a ‘* sporangioles’’ described by Janse, are siao met with occasion- 
ally. From the occurrence of these various stages Professor Weiss 
was SWelinad to infer that a symbiotic relationship existed between 
the fungus and the host-plant similar to that of an existing myco- 
rhiza. With regard to the plant in which the ee pie i he 
was inclined to think that it might have been epiphytic, a view which 
would be supported by the absence of large air-spaces s 
pee: in the young roots of Calamites and in the rootlets of Seigmeuebes 
the same meeting Mr. L. A. Boodle read a paper on the 
structure of the leaves of Pteris aquilina in relation to environment. 
is well known that in dry exposed situations the bracken produces 
inves of a hard dwarf habit, while in very sheltered localities the 
leaves are quite soft, Thi s difference in external characters is ac- 
companied by a aitteranibit in structural characters. The exposed 
leaf has a hypoderm and is a distinctly xerophytic ‘‘ sun-leaf”; the 
other type of leaf is a pronounced ‘ shade-leaf,”’ having no hypo- 
erm, and weakly developed palisade-tissue or no definite palisade. 
A similar difference may occur in deren leaves of the same plant, 
or in different parts of the same leaf when shelter and exposure are 
hao tied localized. A slightly Se plant, when transferred 
a greenhouse, produced shade-leaves only (though the illumi- 
aation was fairly stron OH and in these leaves the indusia were 
considerably reduced. e bracken is thus very plastic in its 
relation to Race 
Art the meeting of the same Society on 19th November, Dr. M. T. 
Masters, F.R.S., F.L.S., gave an abstract of his paper ‘‘ A General 
View of the Genus Pinus,” which was illustrated by specimens of 
cones, and lantern-slides. He stated that the object of the paper 
was to discuss the nature and value of the characters made use of 
in discriminating the various species of Pinus, and to supply ad- 
ditional points of Lagat derived from the ahelomies: structure 
of the leaf and other sources. Reference was made to the tegu- 
mentary, mechanical, tt other leaf-tissues, to the soetion of the 
resin-canals, the number of cells in the endoderm-layer, the sha 
of the central half-cylinder or “ meristele,”’ the imple or branched 
condition of the fibro-vascular bundle, ete. A com 
mentioned, together with those derived from the bud-scales, the 
numbe . of leaves in the fascicle, the conformation of the male 
flowers, and of the cones and cone-scales, the author has framed a 
analytical table of the species, asi although mainly artificial, 
be of assistance hereafter in facilitating the determination o 
the species and in arranging them in more natural ye he 
two main divisions adopted are the thin-scaled Pines or 
and the thick-scaled Pines or et lerieaa! psi he to “the relative 
thickness of the cone-scales. With these are associated so many 
