of Bennettites gibsoniamis, Carr . 445 
inner cavity having disappeared probably by the stopping up 
of the micropylar canal in the usual way. 
Whether this cylindrical process is formed entirely from the 
inner stratum of the testa, while the middle and outer strata 
come to an end at the place where it begins to narrow; or 
whether, while the middle hard stratum dies out, the inner and 
outer strata unite to form the process, I cannot positively say. 
In the former case the testa would probably have been developed 
from two integuments ; in the latter we may assume that it is 
only from one. After weighing all the circumstances I incline to 
the latter view. The question can only be settled by obtaining 
a slice which should be tangential to the surface of the spadix, 
and show the apex of the seed in exact transverse section. 
Unfortunately the only preparation of the kind before me is 
in too imperfect a state of preservation ; its appearance is 
reproduced, as far as it can be, in PI. XXVI, Fig. 7. The 
transverse sections of the apices of the seeds are seen as dark 
circles, sections of solid cylinders consisting of a small-celled 
tissue and surrounded by a single layer of larger cells. Lines 
radiating from one section to another may be distinguished at 
one part of the preparation. Their presence shows that the 
section has passed close beneath the surface of the spadix ; they 
answer to the bounding lines of the superficial areolae. 
As already explained, the ‘ cords,’ the seed-stalks of the spa- 
dix, each terminate in a seed. In each case the vascular strand 
enters the chalaza where it forms a small expansion ; its peri- 
pheral fibrous layer adheres all round to the basal portion 
of the testa (PI. XXV, Fig. 1), and gradually loses its dis- 
tinctive character. But whence comes the closed tissue forming 
the outer rind of the cone, in the depressions of which the seeds 
are imbedded ? My idea once was that this mass of tissue was 
produced by the upward growth of the peripheral portion of 
each seed-stalk forming a wall round the seed, and by the 
lateral fusion of all the seed-containing cavities thus produced. 
But this view can no longer be combined with the account of 
the facts here given. There remains only the possibility, that 
it is the structures with a smaller transverse section, lying 
