ÅND THEIR GERMINATION. 405 
radicle lies in a canal directed obliquely towards the base of the embryo (fig. 9), and is so 
unattached that it may easily be taken out entire. But in Z. nana the radicle is short, 
less oblique in its direction, and the orifice of the canal is not closed, as in Z. marina, 
being covered only by a delicate semitransparent membrane (fig.22). In Triticum, 
Avena, and Hordeum, there is a tubercle immediately under the radicle, which looks not 
unlike a closed orifice. 
As thus described, therefore, the embryo of Zostera marina differs from those of Oryza 
sativa, Zea Mays, &c., only in the cotyledon and its cauliculus being curved by becoming 
bent-downwards, and in the smaller lobe of the radicle being removed from the base of 
the cauliculus (fig. 8 a), which may be the effect of the pressure of the bent cauliculus, as 
it makes a depression in the substance of the radicle. 
Eriocaulone@.—The germination of Eriocaulon septangulare is very singular, differing 
from that of any other plant I have seen. The embryo first protrudes a horizontal 
process, having a small speck on its outer part, consisting of a circular portion of the 
testa, in the same way apparently as Mr. Wilson has described to occur in the germi- 
nation of Lemna gibba (Bot. Misc. i. 145. t. 42) ; but in its after stages it differs in sending 
up a leaf, which is directly away from the cotyledon, as in Juncacee and Ljliacee, and it 
_ cannot, therefore, be compared in this character to either Graminaceæ or Cyperacee. 
Subsequently to the appearance of the first leaf, the horizontal process protrudes a root 
from its under surface, which has no coleorhiza, although it most probably escapes through 
a fissure in the tissue, as the subsequent radicles do. As growth proceeds, the horizontal 
process becomes fissured by the enlargement of the root, which soon breaks through it, 
and its remains are finally left as a root-like process on the root itself. (Figs. 11, 12, 18, 
14, & 15.) så i» : 
On referring to Klotzsch's figures of the germination of Pistia lexensis , I was ned 
ably surprised to find a satisfactory explanation of the germination of Eriocaulon : Fe 
no doubt it will also serve to explain that of Lemna, as figured by Mr. Wilson (loc. > » 
Which is admitted to be very obscure. In Klotzsch's figures the horizontal cap. > D 
doubt the primary radicle, as it has so entirely the appearance of rs Amen > 
Araceæ and their allies, and the same therefore must be the conclusion wit regard E r 
the horizontal process of Briocaulon septangulare (fig. 11) and the un De mai 
 Lemna gibba. But whether this kind of germination is eser rå eene 
a question, because the growth of the radicle is arrested about AER endorhizal and 
- first appears; and possibly such a germination may be eo rd a i 
exorhizal plants, so that Pistiacee and Lemnaceæ may 96% of the loiuale of Pistic 
am. obliged, however, to differ from Klotzsch in his deserip a er u process, 
terensis: what he calls the first leaf, I should undoubtedly Gea å ide calls the 
or perhaps only as the lips of the fissure in the cotyledon; and w3 
ich i sd as being directly away from 
second leaf must, of course, be the first leaf, which is figured as being directly 
the cotyledon, as in Arum. med ER 
nn TIG endorhizal character is here well € rå E e «i 
ever, very thin, and soon disappears. The first leaf of the plum ) 
in, 1853. Taf. ii. figs. Q,R, S. 
* Ueber Pistia ( Abhandl, der K. Akademie zu Berlin, aus dem J. 1852). Berlin 
