208 LEMNACE. 
be considered as having no other spatha than the leaf, itself ? 
It approaches in what is considered its spadix to Pistia. 
The central situation of the stamina contrasted with the 
lateral one of the pistilla invalidates the idea of the stamina 
being lateral developments 
Wilson’s Scutellum is the apex of the nucleus, so curiously 
modified. The three coats mentioned by him amount pro- 
bably to only two, the scutellum itself or its radiated por- 
tion being continuous with the reticulate portion, which form- 
ed originally the cuticle? of the nucleus, the inner mem- 
branous one forming the apex of the embryonary sac. 
The separation of the scutellum depends evidently upon the 
force exerted on it by the growing embryo, and its covering 
its radicle like a cup, depends on the direction of the first 
growth of this coinciding itself with the axis of the inner 
membrane, as well as upon its adhesion with the inner mem- 
brane very equally throughout. 
The perforation of the lower lip of the cotyledon, (radicle) 
by the root of the developing plumule is very curious; it is 
represented both by Wilson and Richard. It is due probably 
to some sufficient obstacle to its escape by the fissure ; 
because this is its mode of existence in the innovations, 
otherwise, in these also it should pierce the lower lip of the 
figure. 
Another argument in favour is, that it does not furnish a 
sheath to the radicle. 
Mr. Wilson thinks that the secutellum is destined to protect 
the embryo from injury while breaking through the external 
coat of the seed, it is necessary to look to this. 
The constancy with which the secutellum adheres to the 
lower lip of the fissure is remarkable, it points out a certain 
laterality in the exit of the plumula, a circumstance of 
some importance, because its adhesion is not of such extent 
as would authorise is to suppose it is the cause of this, neither 
would it be so permanent. 
In these figures there is an obvious defect, for the lower 
