ON NAIAS GRAMINEA DEL., VAR. DELILEI MAGNUS. 809 
_ The rays enclose an equal number of large intercellular cavities, 
each cavity being bounded by the central = per. a al paren- 
chyma at either end. The cavities occur in every internode, 
not always as regular as they are drawn in fig. they 
cecasonally branch at each end so as to enclose a cate inter- 
ellu 
The circumferential tissue of each internode consists of three 
or four rows of elongate cells havin ving a hexagonal outline, with 
sinuous edges. The are all uniform in re ve pest 
* oy) The 
in 
external edge of the outer row of cells is slightly thickened, but I 
cannot hie any epidermal cells. 
osthumous work of Prof. Sere pena Be ge 
aquatic, The Naide are not yet figu iby Ragtanbuth in his 
Icones Flore Germanice et Talveusesy” i. 
V.—Tue Leaves. 
ae leaves grow in tufts at the side of each inter- 
and they are rather more lateral than they are 
represenied in Delile’s figure, reproduced two-thirds the 
original size in Plate 250, fig. 8. In the living state, 
as seen in the water from above, they have a light 
olive-green mys casa oes bor that of the bright 
ied state they 
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Fic. 43. 
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