29 
described and figured by Bruns, and differs in every respect from the 
other Panicew. The scutellum is broader than long, while the plumule 
is covered by a very large epiblast. A peculiarity mentioned by Bruns 
is that the radicle is hollowed out. Owing to the general appearance 
of the fruit and embryo, with its large epiblast and the insertion of the 
scutellum-bundle, also the fact that the flower is monecious, would seem 
to indicate that it does not belong to the Panicew. It might, perhaps, 
be placed with the Oryzew or form an intermediate tribe with Zoysia 
between the Panicew and Oryzee. 
Pennisetum spicatum (figs. 16, 17, 18, Pl. II). The fruit of Pennisetum 
has a very large embryo. The scutellum surrounds the remainder of 
the embryo, although not to such an extent as in the Andropogonea 
and Maydec. The projection opposite the scutellum in fig. 16 is not 
an epiblast, but a longitudinal section through the margin of the scu- 
tellum. A single large radicle is present, whieh consists of one large 
vessel in the center and six small ones surrounding it in the central 
cylinder (fig. 18). The ring around the radicle represents the coleorbiza 
with its attachment to the scutellum. Fig. 17 represents a cross section 
through the plumule, showing the seutellum with its bundle and the 
plumule-sheath with its two lateral bundles. Within is the first true 
leaf. The seutellum-bundle is inserted on the axis at some distance 
from the plumule (fig. 18). 
Chetochloa macrocheta (fig. 19, Pl. III). -The embryo of this nut-like 
fruit resembles in the main other Panicew. The insertion of the 
scutellum-bundle is, however, somewhat closer to the plumule. A deep 
cleft or groove is present between the scutellum and coleorhiza. 
Paspalum pubiflorum glabrum (figs. 20, 21, Pl. III).—The embryo of 
Paspalum resembles that of Pennisetum, although much smaller. It 
possesses a large radicle, and its seutellum-bundle is inserted at some 
distance from the plumule. 
Tribe ORYZEJE. 
To this tribe belong, among others, the genera Homalocenchrus, 
Zizania, and Oryza. Great variation occurs in the size and formation 
of the fruits. The embryo is usually small compared with the amount 
of endosperm, but in Zizania it attains a considerable size. All the 
genera belonging to this tribe have a well-marked epiblast. 
Zizania aquatica (figs. 22, 23 A-B, 24 A-T, Pl. III) (see p. 21).—The 
fruit of Zizania is long and linear, with an epiblast which reaches three- 
quarters the length of the whole fruit. Figs 23 A and B show the rela- 
tive size of embryo and endosperm; A through the plumule, and B 
through the axis or lengthened node. Figs.24 A-T represent a series 
of sections through the embryo from the apex of the plumule-sheath 
tothe main radicle. A and B show the two vascular bundles of the 
plumule-sheath, which at this point are united into one. At C and D 
they have become separated, while at E the plumule-sheath appears as 
