_~ 
OF THE GENUS PINUS. 619 
62. Pinus DENsIFLORA, Siebold § Zuccarini, Mayr, Monog. 
Abietin, des Japan, Reiches (1890), p. 72, tab. 5. f. 17, t. vii. £.5; 
Gard. Chron. March 22, 1894. 
P. tabuliformis, Fortune in herb. 
A well-known Japanese species of which many forms are 
cultivated by the natives. The leaves are channelled on the 
upper surface and have subepidermal resin-canals. On one 
occasion I have seen a resin-canal in the centre of the vascular 
bundle. The two divisions of the bundle are separated by a 
thick layer of stereome-cells. The endoderm-cells are about 36. 
The anther-crest is membranous, truncated, and obscurely 
denticulate at the margin. 
The apophysis is flattish, and the upper border is often 
prolonged into a lancet-shaped point. 
In this species, as in P. rigida, P. halepensis (see p. G08), 
P. Thunbergii, P. cubensis (see p. 603), and P. palustris, the 
male catkins are occasionally androgynous. Mr. Kenjiro Fujii, 
in the ‘Tokyo Botanical Magazine,’ vol. ix. (1895), shows how 
the tranformation of a male into a female flower may be brought 
about by a local increase of nutriment. 
This increase may be effected by pollarding the shoots, and 
thus “ inducing all the nourishment in store to be used in the 
development of the remaining portions of the shoot, especially 
the flowers and the ‘ Kurztriebe’ (spurs) nearest to the wound.” 
Mr. Kenjiro Fujii says that the formation of such flowers is 
mostly limited to the extension shoots (‘ Langtriebe) developed 
from the spurs or Kurztriebe of the last season, aud that such 
transformation of spurs into extension-shoots takes place when 
the extension-shoots are in any way injured, and that the 
Kurztriebe which are transformed into Langtriebe are those 
which stand nearest to the point of injury of the Langtriebe. 
The Japanese botanist just named, by making a series of 
experiments in the Tokyo Botanic Garden, was enabled to say 
that the sex of the flowers is not determined by their position, 
and that it is undetermined till a certain stage of their develop- 
ment, and lastly that “a flower which would otherwise develop 
into a male, has a tendency to become a female when local 
increase of nourishment takes place at a certain stage or during 
certain stages of its development.” 
