Kirx.—On the New Zealand Species of Phyllocladus. 379 
True leaves are only produced in the young state; they disappear before 
the plant attains its third year; rudimentary scale-like leaves, from the 
axils of which the broad foliaceous organs are produced, are developed on 
the branches, but soon fall off. The broad fern-like foliaceous expansions, 
which take the place of true leaves, are by some termed '*cladodia," by 
others ** phyllodia," according to the point of view from which they may be 
regarded, whether as consisting of abortive flattened branches when the 
former term is applied, or of a flattened and expanded petiole, or of coherent 
leaves, or of an expanded combination of leaves and petiole—to either of 
which the term phyllodia is applied. As, however, these organs develope 
flower-buds, a process of which true leaves are incapable, it is evident that 
they cannot be regarded merely as connate leaves, or any modification of 
leaves and petioles, so that the term cladodia is most closely applicable. 
The cladodia are thick and coriaceous, more or less rhomboid in shape, 
with the upper margin more or less toothed, lobed, or erose; the lateral 
veins radiate from a central vein outwards, so that the organ bears a 
general resemblance to the pinnule of a large species of Adiantum. In 
P. glauca and P. trichomanoides the cladodia are arranged distichously on a 
rachis consisting of a peculiarly modified branch, and present the appear- 
ance of an ordinary pinnate leaf with alternate leaflets, forming in fact 
pinnate cladodia, the greater portion of which fall off when the lateral 
expansions have performed their function. But in P. trichomanoides during 
autumn or early spring a whorl of new cladodia is developed at the apex 
of an old rachis, the lateral cladodes of which soon after drop off and the 
rachis becomes a permanent branch. In the spring, male amenta are 
produced at the apex of a branch and surrounded by a whorl of cladodia 
with the lateral expansions greatly reduced in size and carrying female 
cones. This arrangement, however, is liable to several unimportant 
modifications. In P. glauca the process is somewhat different ; a terminal 
rachis becomes elongated and thickened, assuming the character of a true 
branch ; in the following spring the axis is slightly elongated and densely 
clothed with recurved rudimentary leaves surmounted by a whorl of large 
cladodia, which carry female flowers instead of lateral cladodia in the lower 
part of the rachis. 
The female flowers are arranged in amenta, which are one-flowered in 
P. trichomanoides, two- to four-flowered in P. alpina, and from ten- to twenty- 
flowered in P. glauca. Each ovule is imbedded between two modified leaves, 
which become thickened and fleshy as the fruit approaches maturity, and in 
P. glauca at length woody. In that species the numerous nuts are arranged 
in slightly interrupted spirals, and in all the species the nuts are much 
compressed, and have the lower part invested by an arillode, which is most 
conspicuously developed in P. alpina. 
