

1905.] Lagenostoma, a Type of Pteridospermous Seed. 249 
more especially in photos. 3 and 4, and less distinctly in photo. 1. It is 
difficult to judge of the exact number of lobes in such a cast, in which 
only one side of the seed is visible, but in several instances (Plate 2, 
fig. 3) in which the apex of the seed is particularly clear, there appear to be 
six lobes. The number is not, however, necessarily constant. In L. physoides, 
the species which stands nearest to that under discussion, the number varied 
from 10 to 11, and in the other species, Z. Zomazi and L. ovoides, there 
are indications that the number of the fluted ridges at the apex, corresponding 
to the lobes in Z. physoides and L. Kidstont, was not always identical in every 
specimen. It is known from the investigations of petrified material of similar 
seeds that these lobes or flutings correspond to the chambers of a dome-like 
structure, the canopy,* which surrounds the pollen chamber. 
Of the hundreds of these seeds which have been examined, whether in the 
Glasgow or the British Museum specimens, every one has proved to be naked. 
At the stage of their development at which they are there represented—a 
stage which appears to be the same in practically every instance—there is 
reason to believe that the seed was not enclosed in any protective organ, 
similar to that described as the “ cupule ”f of Z. Zomaxz, which played such 
an important rdle in the correlation of that seed with Lyginodendron. 
In only one instance (Plate 2, fic. 4; Plate 1, photo. 4) has the presence of 
any structure been detected which could be regarded as of this nature, 
and here the organ in question does not obviously subtend, although 
it is in close proximity to a seed. The preservation is not particularly good 
and its form is not very clear. It appears to consist of a circular or oval 
ribbed-sheath, probably of a foliar nature, divided distally into a large 
number (considerably more than 15) of rather blunt, lanceolate teeth, 
each about 0°5 mm. in length. The length of the whole sheath is about 
5 mim. 
Although there is no Upper Carboniferous.foliar organ with which I am 
acquainted, that at all agrees with this sheath-like body, I am not disposed to 
attach any special importance to its occurrence here in the neighbourhood of 
a detached seed. It may be that the seeds of Z. Kidstoni, like those of 
L. Lomaxi and L. Sinclairi, the latter to be described here subsequently, 
were enclosed in a “cupule” at an earlier stage in their development than 
that represented in these specimens, and that, like Z. Lomaai, the mature 
seeds may in most cases have been naked. On this assumption, the organ 
under discussion might be interpreted as of the nature of a “cupule.” This 
single instance, however, hardly furnishes reliable evidence on this point, and 
* Williamson, zbid., p. 235 ; Oliver and Scott, cbid., p.,208. 
 t Oliver and Scott, zbid., p. 215. 
VOL. LXXVI.—B. 8 
