TRANSACTIONS OF SECTION K. 927 
trace consists of 6 trachex in the form of a tangentially elongated group, and 6-8 
rows of radially disposed centripetal scalariform vessels. The traces consist only 
of primary elements, and pass outwards through a medullary ray of the secondary 
wood. 
Professor Bertrand compared the Hardinghem specimen with Diploaylon stems 
from Oldham, Halifax, and Burntisland, and with a Sigillaria of the Leiodermaria 
eee section, S. sprnulosa. In S. spinulosa the leaf-traces are given off 
rom the same position on the corona as in the ribbed stem, but in the former 
species the corona consists of separate groups of tracheids as distinct from the 
continuous band in the Hardinghem stem. In the Leiodermarian species, as 
Renault has shown, the leaf-traces consist in part of secondary xylem. 
In the Diploxylon stem from Halifax and Oldham the leaf-traces are given off 
from the middle of a sinus of the corona, as in the new Stgillaria, but in the 
Burntisland Diploxylon they have a lateral origin, as in Lepidodendron selaginoides. 
3. On a biserial Halonia belonging to the genus Lepidophloios. 
By Professor F. E. WEIss. 
At the Bristol meeting of the British Association, Dr. D. H. Scott exhibited 
photographs of this Ha/onia from the Hough Hill Colliery, Stalybridge, and 
pointed out the agreement of its well-preserved internal structure with that of 
Lepidodendron fuliginosum of Williamson, Dr. Scott had most kindly and gene- 
rously allowed the author to undertake the further examination of this specimen, 
and this completely confirmed the identity of the internal structure of this Halonia 
with that of Williamson’s Lepidodendron fuliginosum. Williamson retained this 
name in his ‘ Memoir,’ pt. xix., published in 1893, though Cash and Lomax had 
shown conclusively, at the meeting of the British Association at Leeds in 1890, 
that this type of structure was revealed by a specimen showing undoubtedly 
Lepidophiovos leaf-scars, and though Williamson’s Lepidophioios, figured in pt. xix., 
also shows the stem structure of the fuliginosum type. The same structure is 
shown also by stems of the ordinary multiseriate Halonias, which, as Kidston and 
Potonié have shown, belong undoubtedly to the genus Lemdophloios. Stems, 
therefore, showing the structure of Lepidodendron fuliginosum (Williamson) should 
be referred to the genus Lepzdophloios, 
The fruiting branches of this genus, however, termed Halonia, or halonial 
branches, have usually a number of rows of spirally arranged tubercles. The 
Hough Hill Halonia has only two rows of fructigerous tubercles. Hence it would 
by some palzobotanists be classed as Ulodendroid, but it seems better to call it a 
‘biserial Halonia,’ since the name of Halonia has been reserved by Kidston and 
others for the fruiting branches of Lepidophloios, and also because its elevated 
tubercles distinguish it from the usually depressed Ulodendroid scars. As the 
Hough Hill Halonia shows no leaf-scars, the author has sought for confirmatory 
evidence for his conclusion that Lepidophloios may possess fruiting branches with 
two rows of fruit-bearing tubercles. The Lepidophlotos figured by Williamson in 
his nineteenth ‘ Memoir’ (figs. 830 to 38), and coming from the same locality, is 
described as possessing two rows of halonial tubercles, and this is confirmed by 
two pieces of this specimen preserved, one in the Williamson collection in the 
British Museum, and another in the Wilde collection in the Manchester Museum. 
The author also submitted photographs of two other biserial Halonias showing dis- 
tinct Lepidophioios leaf-scars, one from the Williamson collection (No. 1946B) 
at the British Museum, and one presented by Mr. Dawes to the Manchester 
Museum, Owens College. These, he considered, confirmed his conclusion that the 
biserial Halonia from the Hough Hill Colliery was also a fruiting branch of 
Lepidophioios, 
