Mr. J. Miers on Ephedra. 435 
fere). In Tazxus, however, if we consider the outer coating of 
its pistil to be a carpel, which grows into an osseous shell, then — 
its ovule is perfectly devoid of any integumentary envelope, as 
in Pinus, and in like manner it produces a perfectly naked 
seed*; and, according to the masterly analyses of Taxus by 
Mirbel and Spach+, the facts of which have been confirmed by 
Schleiden, its ovule has constantly three foramina in its apex, 
leading into as many embryoniferous cavities in the amnios, 
after the manner of other true Conifere. This is perfectly at 
variance with all that we find in the Gnetacee. 
With the Cycadacee the dissimilarity in these respects is still 
more striking. The existence, however, of a suspensor in its 
seeds has greatly favoured the idea of the close affinity of Gne- 
tum with this family: the coincidence is unquestionable; but 
this circumstance is of little import upon its own merit, for we 
may conceive the possibility of its occurrence, as we find it in 
Gnetum, in any family of the highest order of development. The 
growth and structure of the seed in Cycadacea, as demonstrated 
by Miquelt, present many peculiarities of which we have no 
parallel in the Gnetacea. If we regard in its proper light the 
outer covering of the pistil, and the thick fleshy and coriaceous 
shell of the seeds of the Cycadacee to be the growth of a true 
earpel, it will be evident that the erect nucleus enclosed within 
the pistil and the seed contained within the carpel are deficient 
of any proper integument ; and under this point of view both may 
be considered to be perfectly naked—a condition widely different 
from that of the Gnetacee, where both the ovule and seed are 
covered by two distinct integuments. Miquel, who considered 
the pericarpial covering of the fruit to be the testa of the seed 
lined with an adherent inner integument, notices that the latter 
in its early stage is crowned by a broad areolar callus, which he 
calls its chalaza; this is marked by a circular ring of perfora- 
tions, which open into as many small cavities, in each of which 
is generated a distinct thread, coiled up and bearing at its lower 
extremity an embryo-sac: all these sacs descend into the am- 
niotic body, where only one of them is fertilized; this fertilized 
sac finds its way out of the amnios into the body of the nucleus 
_ * From the analysis of Torreya taxifolia, as given by Sir Wm. Hooker 
(Icon. 232, 233), it would seem that its carpel is at first pervious at its 
summit, and is furnished with an erect atropous ovule, provided with two 
very distinct free integuments, of which the primine rwards becomes 
agglutinated to the carpel in the fruit, while the secundine remains co- 
herent with and enters deeply into the plicatures of the ruminated albu- 
men. Should this analysis of the ovary be confirmed, it would show that 
Torreya cannot belong to Taxinee, but is more allied to Myricacee, 
+ Ann. Sc. Nat. 2 sér. xx. 257. 
t Ann. Se. Nat. 3 sér. iii. 193, pl. 8. 
