ANATOMY OF THE JULIANIACE X. 149 
Their investigation, has revealed certain peculiarities, which may be due to their 
immature condition, though possibly they may mean distinct characters. The scleren- 
chyma-bundles are just as characteristically developed, but the tissue internal to them 
did not show nearly so great a thickening of its walls. The crystalline layers are very 
indistinet—entirely absent in some places. 
(v.) THE EMBRYO. 
Satisfactory material of the embryo was only obtained in Juliania adsiringens (Nelson, 
n. 1827). The hypocotyl, as seen in a transverse section through the fruit, is triangular 
with rounded angles. It contains four rudimentary vascular bundles, which at this 
stage contained no lignified elements whatever. In the phloem-portion of each bundle 
a single resin-canal is already developed, the secretory cavity being lined by a layer of 
elongated cells. "This early development of the resin-canals is noteworthy, and shows 
that the plant commences to exercise its secretory function even before the ordinary 
conducting elements are fully differentiated. The ground-tissue of the hypocotyl is 
made up of rounded cells with thin walls. The epidermal cells are small. 
The main mass of the cotyledons is composed of elongated palisade-cells, surrounded 
by an epidermis of small cubical cells. All the cells are densely crowded with starch- 
grains. 
(vi.) ANATOMICAL DIAGNOSIS OF THE ORDER. 
The following are the chief points of agreement exhibited by the different members 
of the Julianiaceæ :— 
(i.) Leaves more or less typically bifacial, the tissues often showing a distinct strati- 
fication ; no hypoderm; palisade-tissue a single layer of much elongated narrow cells. 
(i) Epidermis of the leaf often with a striated cuticle; stomata almost invariably 
confined to the lower epidermis, without subsidiary cells. 
(iii.) Simple uniseriate clothing-hairs of a slightly varying type ; glandular hairs with a. 
short stalk and a more or less club-shaped glandular portion. 
(iv.) Vascular bundles of the leaf with little xylem and no accompanying sclerenchyma ; 
à resin-canal in the bast of each bundle. 
(v.) Oxalate of lime only in the form of clustered crystals in the leaf. 
(vi) Petiole at its base with a ring of bundles open on the upper side; at its apex 
with a complete ring. , 
(vii) In the stem cork-development probably subepidermal; cortex commonly with 
scattered thickened and sclerosed cells. 
(viii) Resin-canals in the secondary bast enveloped externally by arc-shaped groups 
of obliterated phloem. : 
(ix.) Wood with narrow medullary rays, the cells of which bear simple pits ; wood- | 
parenchyma practically absent; wood-prosenchyma with slit-shaped simple pits, often 
Septate ; vessels rather numerous, for the most part with simple perforations ; their 
walls bear large simple pits when in contact with elements of the medullary rays, while 
at other points there are simple or bordered pits. 
(x.) Pith composed of spherical cells with simple pits. 
