780 REPORT—1904. 
bibractensis, where the last chain at its emission unites the two polar marginal 
“points. These remarkable peculiarities correspond at the emissions with an 
unopened marge. 
4. On the Presence of Parichnos in Recent Plants. By T. G. Hitt, 
If a mature sporophyll of Isoctes Hystrix he examined, there will be seen in the 
lateral expansions of its base two longitudinal cavities containing a certain amount 
of mucilage, and situated one on each side of the vascular bundle in close proximity 
to the sporogenous mass. : 
By the examination of sporophylls in different stages of development, it may 
be ascertained that the above-mentioned canals arise by the mucilaginous degenera- 
tion of two strands of parenchyma. 
The structure in question does not extend into the cortex of the stem, but is 
confined entirely to the base of the sporophyll, its limits seemingly depending upon 
the extent of the sporangium. 
Whether the same features obtain in sterile leaves has not been determined, 
owing to the lack of material. Indications of a similar structure were observed in 
other species of Isoetes. 
It is suggested that these strands of degenerating tissue, and the resulting 
mucilage-containing canals of the mature leaf, represent the parichnos occurring in 
Lepidodendron, Sigillaria, Lemdocarpon, &e. 
5. The Anatomy of Psilotum triquetrum. Zy Miss Sreinim O. Forp. 
Psilotum triquetrum consists of a much-branched aerial stem and rhizome. 
The leaves are much reduced and have no vascular supply. There are no roots. 
The plant is monostelic throughout. At the base of theaerial stem a protostele 
is found, and this, higher up, may be succeeded by a medullated stage with no 
inner phloem or endodermis. Secondary tracheids may occur (Boodle). In the 
aerial branches a central core of sclerenchymatous fibres is found, surrounded by 
xylem with radiating groups of protoxylem. In the rhizome the xylem forms an 
irregular mass with no fibres, and the protoxylem consists of ordinary scalariform 
tracheids, 
The phloem throughout is feebly developed, and lignification of this tissue may 
occur in the aerial stem. 
A three-sided apical cell is present both in the aerial stem and in the rhizome. 
From the nature of the sporangial apparatus the Pszlotacee have been regarded 
as possessing a close affinity with the fossil Sphenophyllales. There is also a 
strong resemblance, anatomically, to some of the fossil Lycopods, especially to the 
stem of Lepidodendron mundum, as well as to the axis of the cone of Lepidostrobus 
Brownii. 
6. Seed-coats of Cycads. By Marir C. Storrs, Ph.D., B.Se. 
A number of species in various stages of the ovules of Cycas, Zamia, Macro- 
samia, Ceratozamia, Encephalartos, Bowenia, and Dioon were examined. 
The usual description of the integument as a single one, differentiated into two 
layers, an outer fleshy and an inner stony, is found not to hold good. In all the 
above-mentioned genera there is also a soft inner integumentary layer, which is 
sometimes greater in diameter than the outer fleshy layer ; frequently it and the 
nucellus are crushed together by the growing prothallium, but this is by no means 
always the case ; sometimes it remains fresh quite late. 
Two series of vascular bundles run in the ovule, and it is proved that the 
inner series, frequently described as ‘nucellar, belongs to the soft inner layer of 
the integument. These bundles do not invariably die out at the region where the 
nucellus becomes free from the integument, as hitherto supposed, but in more than 
