i8 
Scott —On the Fertile Shoots of 
The fertile shoot is bilaterally symmetrical ; it consists of a naked main 
axis, containing a flattened stele, and bearing distichously arranged bud-like 
branches, lying in the plane of the major axis of the main shoot. Each 
branch has a cylindrical, medullated stele, and bears numerous spirally 
arranged bracts, with a single vascular bundle of mesarch structure. 
A large bract, lying outside the others, may probably be the prophyll 
of the branch. In one case an appendage, apparently of a different kind, 
was observed, which might possibly be the pedicel of a seed. 
In general morphology, and in the detailed organization of the lateral 
buds, the fertile shoots show a close agreement with the distichous forms of 
Cordaicinthas , described by Grand’ Eury, Renault, and Bertrand, and are 
clearly of the same nature. The sex of the inflorescence has not been 
determined, as no reproductive organs are attached, but the probability 
is in favour of its having been a seed-bearing organ. It is associated with 
the seeds named Mitrospermum compression by Dr. Agnes Arber. 
Two shoots of a different kind are then described, which appear to 
have been of the nature of vegetative buds, for their structure is that 
of a stem, and they bear closely packed polydesmic leaves, of a Cordaitean 
type. The leaf-traces of these shoots are single where they traverse the 
wood, only dividing in the cortex. These shoots also are associated with 
seeds of Mitrospermum compressum . 
Lastly, two larger stems of the Mesoxylon type are recorded, in which 
the leaf-traces are likewise single in passing through the wood. These 
stems and the bud-like shoots are placed together in a new genus, 
Mesoxylopsisy differing essentially from Mesoxylon in the leaf-trace being 
single and not double. The one known species is named Mesoxylopsis 
Arber ae. 
The equally intimate association of Mitrospermum compressum with 
the Cordaianthus of Mesoxylon multirame on the one hand, and with the 
bud-like shoots of Mesoxylopsis Arberae on the other, raises grave doubts as 
to the value of the evidence from association, always so uncertain in palaeo- 
botany, and doubly treacherous among the crowded and intermixed frag- 
ments of the coal-ball petrifactions. It was, however, clearly desirable 
to ascertain whether the seeds of the two categories were in fact specifically 
identical. Dr. Agnes Arber, F.L.S., to whom I have submitted sections 
showing the seeds associated with both kinds of shoots, kindly allows me to 
quote her opinion, as follows : ‘ The sections of the seeds all seem to me to 
be typical Mitrospermum compressunty and I see no reason for separating 
those in the three slides in which they are associated with Mesoxylon multi- 
ramel At the same time Dr. A. Arber calls attention to a remark in her 
preliminary note on this seed (A. Arber, 1910, p. 393 ) : ‘ There is sufficient 
variation among the specimens, both in dimensions and structure, to 
suggest that Cardiocarpon [now Mitrospermum ] compressuniy instead of 
