144 ^°^ on the Sporophyll of Lycopodium inundatum. 
a thin membrane which projects downwards from the stalk of the 
sporophyll and at its distal extremity bisects the dorsal lobe. An 
absolutely median radial section through the sporophyll would pass 
through this descending membrane and would thus not have a 
peltate form ; sections on either side of the median line have the 
conformation figured, sometimes even while still including a portion 
of the vascular bundle, as in text-figure 5 of my paper. The des¬ 
cending membrane, as in L. cernuum, is left by mucilaginous 
degeneration in the lower portion of the stalk, only the epidermal 
layer remaining (Fig. 19, me). Since the mature form is arrived at 
in this way in L. inundatum, it appears advisable to refrain from 
applying the term peltate to the sporophylls of this species. I did 
not use it reference to L. inundatum and I attempted to avoid it 
throughout my paper, since I do not consider that sporophylls such 
as those prevailing in this genus are strictly comparable with the 
truly peltate sporophylls of Equisetum, &c. 
In L. cernuum, in addition to that portion of the dorsal lobe 
which, as in L. inundatum, clavatum, &c., is left by mucilagenous 
degeneration, Dr. Lang has described a small free flap (cf. Fig. 1, 
p. 358 of his paper). Since my examination of the sporangium¬ 
bearing organs of Lycopodium was practically confined to mature 
forms, I w r as unable to distinguish this differerence in development. 
I understand that Dr. Lang refers only to this small free 
portion as the dorsal flap, whereas I, on the other hand, have so 
described the whole of that portion of the leaf-lamina which 
extends dorsally below T the level of the sporophyll axis; the 
possession of this additional downgrowth appears to me to be but 
another instance of the greater complexity of the cone of this 
species. Both Dr. Lang and I have already laid stress on the 
conception that this greater complexity is correlated with the 
vertical approximation of the whorls of the sporangia. 
The remarkably interesting results of a detailed comparison 
between the cones of L. cernuum and Spencerites by which Dr. 
Lang has once more drawn attention to the striking resemblance 
between these two forms seems to me another strong argument in 
favour of the primitive position of this species in the genus 
Lycopodium ; I still consider “the L. inundatum type of cone 
reduced from that of L. cernuum" 1 and intermediate in position 
between the latter and simpler species of the genus. The argument 
on page 54 of my paper concerns the arrangement of the mature 
1 Lang, W. H., l.c., p. 363 (footnote). 
