206 
CONTRIBUTIONS TO BOTANY. 
growing straightforwai'd in the same centrifugal direction ; the 
chalazal point is consequently identical with the hilar or funi- 
cular point of attachment of the ovule, and therefoi’e there exists 
in no case any simple raphe, and but rarely any tracheal vessels, 
except those which exist in the funiculus ; the growth of the 
ovular tunics is just the same as in the anatropal ovules. Spiral 
vessels, however, are occasionally seen, extending radially beyond 
the region of the chalaza, through the tissues of the primine, as 
sometimes occurs in like manner in anatropal ovules. 
In the foregoing details of an anatropal ovule, I have men- 
tioned the raphe only as appearing in the shape of a simple cord 
imbedded in the tissues of the primine, traversing it upon its ven- 
tral side from the funicle to the chalaza, where it disappears. 
But other distinct kinds of raphe occur : it frequently happens 
that, besides the main cord just mentioned, other branches of 
the nourishing vessels, as they issue from the funicle, spread 
themselves in distinct nervures over the whole area of the testa : 
sometimes, as I have shown in the Styrace<B, these ramifications 
are extremely numerous, the delicate spiral threads being loose 
or in lax bundles, spread throughout the testa, like a fine web ; 
. this also occurs in the testa of Ophiocaryon, Olea, and many other 
seeds. In other cases, again, we find these ramifications radiating 
in distinct nervures from the chalaza and anastomosing over the 
surface of the seed ; this is instanced in the Almond, to which 
Prof. Lindlcy has alluded as presenting an anomaly not readily 
accounted for; its nature is, however, easily explained. The 
Almond is generally described as being exalbuminous ; for if we 
cut through the seed, we come immediately upon the large 
fleshy embryo, which is found enveloped by an apparently single 
flexible coating, but which on examination is seen to be composed 
of different integuments agglutinated together. The inner coat- 
ing is easily detached by a blunt point introduced beneath it, 
by which means it may be separated entire ; it is then very thin, 
almost membranaceous, opake, w'hite, not reticulated, but appa- 
rently formed of minute aggregated cells, and perfectly homo- 
geneous in all its parts; it is somewhat thickened over the 
radicle, and comes away from the chalaza without discoloration, 
as easily as from all other parts of the surface; in fact, notwith- 
standing its attenuation, it presents all the characters of albumen. 
Intermediate between this and the external integument is a deli- 
cate membrane, which is separable with some difficulty, this being 
the tegmen, finely reticulated ; the external testa is much thicker, 
opake, with a rugose surface. Upon raising the tegmen, we 
find, lying beneath it, several bundles of spiral threads in ana- 
stomosing bands, so loose that each fibre can be easily drawn 
out separately ; these bundles of vessels constitute the branching 
