PEOFESSOE HENEEET ON THE ANATOMY OF VICTOEIA EEOIA. 
483 
lignified prosenchymatous cells, surrounded by vessels or ducts, the orifices of which form 
a kind of ring at the point where the central axis joins the cellular rind. This struc- 
tm’e prevails in all the Monocotyledonous roots I have examined*. 
In Dicotyledons, on the contrary, the woody substance of the root, like that of the 
stem, always has the vascular elements in the central region and the woody tissue out- 
side it ; in fact the root of a Dicotyledon corresponds essentially with the stem, omitting 
the central pith and the liber-structure of the bark. In Victoria the cross section of a 
root (Plate XXXI. fig. 63) shows that the centre is occupied by the vascular structure, 
the large open ends of the vessels appearing scattered in a central cylindrical region, 
which is hounded externally by a ch’cle of compact, small-celled cellular tissue, which 
may be compared with the woody portions of the vascular bundles of ordinary Dicoty- 
ledons. Perpendicular sections made through the region where the roots pass out from 
the stem, show that the bundles of vascular tissue destined for the root become collected 
together into a sohd cord before entering it, and they then occupy its axis ; while simi- 
lar sections of the origin of Monocotyledonous roots show that a hollow cylinder of 
vascular tissue arises from the ‘ fibrous layer ’ of the stem and passes out in this cylin- 
dric form, its centre heing occupied hy tissue passing gradually from parenchymatous 
into prosenchymatous, but directly continuous with the central region of the stem. The 
structure of the root of Victoria is therefore according to the Dicotyledonous type. 
The stiTicture and germination of the seeds of Nympheeaceae have long attracted the 
notice of systematic botanists, and very different views have been entertained on this 
subject. Victoria has been observed in reference to these matters, especially by Teecul, 
Planchon, and the authors of the ‘ Flora Indica.’ My own observations are, however, 
at variance in several respects with those of all these observers, more particularly in 
regard to the phenomena presented in germination. 
In the ripe seed we find the emhryo, enclosed in its special sac (amnion), lodged in a 
cavity excavated in the perisperm (Plate XXIX. fig. 19). It is of a depressed conical 
form, the fiat base exhibiting a small ‘ boss ’ or blunt elevation in the centre, which is 
the radicle, and this of course looks towards the surface of the seed. The position of 
the radicle is visible through the amnio tic coat (fig. 20 a), hut it is not until this is 
removed that the Dicotyledonous structure of the embryo is clearly seen. We then 
find the conical embryo (fig. 21) presenting a vertical groove running oA^er the summit 
and down each side, dividing it into two halves, the two cotyledons ; and the groove ends 
in a kind of notch at each side of the base, next the radicle. Separating the cotyledons 
in the line of the commissure (fig. 21 d, e\ we perceive that they are excavated inter- 
nally, so as to form, Avhen applied together, a somewhat globular or very convex lenti- 
cular case, enclosing the plumule. The plumule, placed centrally and directly over the 
ladicular papilla, is a fleshy body, somewhat compressed in the direction parallel to the 
A more particular account of this character is contained in a former- paper read in 1847 before the 
British Association, and published in the ‘Annals of Natural History,’ Series 2, vol. i. p. 180. 
