33 
Beckmannia eruceformis (fig. 60, Pl. VI), Bulbilis dactyloides (figs. 58 
and 59, Pl. VI), and Leptochloa imbricata (fig. 56, Pl. VI) have about 
the same charaeteristies. 
Tribe FESTUCEJE. 
The embryo of the Festucew is usually small. There is, according 
to Bruns, great variation in the presence and absence of an epiblast 
in this tribe. 
Uniola latifolia (fig. 61, Pl. VII)—A broad epiblast reaehes about 
half the length of the plumule. The scutellum-bundle is inserted on 
the axis at some distance from the plumule, while the single radicle is 
turned obliquely outwards. 
Desmazeria sicula (fig. 63, Pl. VII), Cynosurus eristatus (fig. 64), and 
Panicularia aquatica (fig. 62, Pl. VII) all have the epiblast well marked. 
The scutellum-bundle differs from that of Uniola in being inserted 
directly at the base of the plumule. The axis terminates in a single 
radicle. 
Tribe HORDE. 
The tribe Hordew may be characterized as having large fruits. The 
embryo usually has several radicles and a lateral bud in the axil of the 
plumule-sheath. A transition seems to take place between those with- 
out an epiblast, as in Hordeum (fig. 65, Pl. VII), and those with a dis- 
tinetly formed epibiast as in Triticum (fig. 69, Pl. VII). 
Hordeum vulgare (fig. 65, 66 A-H, Pl VII. The fruit of Hordeum 
vulgare has many peculiarities not found in other grasses, There are 
two, and in some parts three, layers of gluten cells, while in nearly all 
grass fruits there is only one. This embryo often has, besides its main 
. radicle, eight secondary ones, three on each side of the scutellum and 
two in front. In the axil of the plumule-sheath next the scutellum 
there is a large lateral bud (see p. 20). By examining figs. A-F it will 
be seen that the scutellum-bundle is composed of two strands which 
unite just before their insertion on the axis. The scutellum is inserted 
on the axis at the base of the plumule, a secondary radicle also emerg- 
ing from it at this point, thus making the axis very short. At fig. 65 
the bundles may be seen whieh belong to the first and second leaves 
and the vegetation point. Those of the plumule-sheath not being in 
the same plane are not represented. A transverse section through the 
upper part of the plumule (fig. 66) shows the opening in the sheath 
opposite to the scutellum and the two bundles situated laterally. 
Within is the upper part of the first true leaf. The seutellum shows 
a peculiar groove ou its convex side next to the endosperm (fig. 66, A, B). 
B shows a similar condition a little lower down through the plumule. 
At C and D the position of the first leaf opposite to the plumule-sheath, 
the second opposite the first, and the third opposite the second, accord- 
ing to the true distichous arrangement of all grass leaves may be noted. 
20946— 
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