CONTRIBUTIONS TO BOTANY. 
163 
I have to make an essential correction in regard to the tubillns ; 
from recent examinations of the seeds of Ephedra dumosa (in 
which the seminal integuments are somewhat thicker) and of 
immature seeds of E. Americana, lately obtained, it is seen that 
the tubillus is expanded below, like an inverted funnel, quite 
free from the apical gland, which it surrounds, and is continuous 
with the outer integument, of which it is a simple extension. 
In the cases previously observed, this dilated portion was so ex- 
tremely delicate, and adhered so closely to the gland, that the 
tubillus seemed to rise out of it. The fact, as above stated, is 
now beyond all doubt. 
I have again examined carefully the suspensor in Ephedra, 
but can discover no trace of those embryo-sac-bearing filaments 
which are found in Gnetum and Wehvitschia. The tubillus, as 
above stated, is a prolongation of the outer integument ; the red 
fleshy gland is attached to and closes the mouth of the inner 
integument. To a small point in the centre of this gland is 
attached the white cylindrical and tubular suspensor, hemi- 
spherical at its apex, the lower extremity of which descends 
upon and adheres firmly to the upper part of the albumen, thus 
forming a kind of white cap upon it for a quarter of its length. 
This suspensor is capable of considerable extension ; and when 
cut open along one side and examined under the microscope, 
it is found to consist of a loose mass of condensed and extremely 
fine fiocculent tissue, confusedly huddled together like paper- 
pulp, without the slightest trace of any of the coiled filaments 
seen in Welwitschia and Gnetum, or any vessels whatever. The 
albuminous mass is just the length of the embryo, and does not 
extend over the summit of the radicle, which is quite naked 
within the hollow cylinder, but it disappears gradually, and 
becomes lost in the fiocculent substance of the suspensor. be- 
coming at last so far attenuated as to disappear in the form of 
separate granular cells. From these facts we may infer that 
this suspensor is only a portion of the amniotic body which has 
not been obliterated, or in which albuminous grains have not 
been deposited — a condition of development clearly indicated by 
the acute sagacity of the late Mr. Robert Brown*. 
* “ In other cases the albumen is formed by the deposition of granulated 
matter in the cells of the nucleus. In some of these cases, the membrane 
of the amnios seems to be persistent, forming, even in the ripe seed, a 
proper coat for the embryo, the original attachment of whose radicle to 
the apex of this coat may also continue.” (Gen. Rem. p. 57.) This view 
applies as well to the origin of the vitellus in many seeds as to the peculiar 
development existing in Ephedra ; and it is probable that future researches 
may show the existence of an analogous development in other cases, and 
may lead to a knowledge of the true affinities of the Gnetacece, which we 
have yet to learn. 
