PROTEACEZ. 403 
trachez of the medullary sheath; the existence of sclerous cells 
disseminated in masses through the pith, and even in the medullary 
rays and cortical parenchyma. These peculiarities, well worth 
particular study, are rarely found united in a single plant, as occurs 
in certain cultivated species of the genus Stenocarpus. 
But the leaves are the vegetative organs to which most attention 
has been devoted by botanists and paleontologists. They never 
possess stipules. They are almost always alternate, though some- 
times opposite, as in Xylomelum, or verticillate, as in several species 
of Andripetalum.! The blade is usually thick, coriaceous, and dry, 
sometimes flattened, sometimes rounded or cylindrical. It is pretty 
frequently entire, still oftener incised in some way or other; some- 
times toothed, sometimes pinnatifid or pinnatisect. It may be 
simply bilobed, with equal or unequal lobes and an empty sinus 
between them; or there may project into the sinus (as in Delobeia) 
a gland representing the modified end of the midrib. Finally, in 
some genera the leaves are quite pinnate,’ or one may find both 
simple and compound leaves on one and the same branch; for in 
this order we often find these organs polymorphous on the same 
plant or branch. In a given species, then, we may find some leaves 
simple, and others much divided, recalling those of a Leguminose, 
Araliad, or even Umbellifer. The apex of the leaf is often mucro- 
nate or spinescent; the upper surface is usually smooth and gla- 
brous, while the lower is often covered with a whitish or brownish 
down. The form of the leaves and the condition of their surfaces 
result in a peculiar distribution of the stomates,’ which here possess 
1 This character does not appear constant in 
this genus; it is, however, one reason for think- 
ing that certain oceanian Helicias should be 
referred to Andripetalum. Hence, perhaps, it 
is to the latter rather than the former genus 
that we should refer the genus Cylindria of 
Lovretzo (Fl. Coch., ed. Ulyssip., 1790, 69), 
which has opposite leaves, 4-merous flowers, and a 
double perianth (?), to the inferior divisions of 
which are superposed the stamens. This genus 
was attributed by Kania (in Ann. of Bot., i. 
892) to Oleinee; but perhaps, thinks R. BRown 
(in Trans. Linn. Soc., x. 224), this is through 
some confusion. It does not appear to us im- 
possible that Cylindria may, after all, belong to 
Lorantha or Ol ; for it differs from 
Helicia in having a double perianth. 
? The divisions are not, however, usually sepa- 
rated by distinct articulations. 
3 This distribution depends mainly on the 
form of the blade. Where it is flat and mem- 
branous, the stomates are confined to the lower 
face, as in Ayastachys, Cenarrhenes, Lambertia, 
Symphyonema, Stenocarpus, Lomatia, Banksia, 
and Dryandra, as well as in many species of 
Grevillea. But several species of this genus 
have stomates above as well as below. In the 
flat-leaved species of Orites they are only found 
below; but where the leaves are cylindrical 
they are all over them, This last is the case in 
the leaves of Hakea, Petrophila, Conospermum, 
Franklandia, Stirlingia, Bellendena ; but the 
blade and its lobes are not always rounded or 
cylindrical, and the stomates are found on both 
surfaces of the leaves of Persoonia and Synaphea, 
which are often flattened. Protea has long been 
cited for its poverty in stomates, though the 
blade is firm and coriaceous. 
DD 2 
