CF COAL-MEASURE PLANT-IMPRESSIONS. 177 
Diagnosis.— Cones similar to those of L. variabilis, Lindl. & Hutt., but 
heterosporous. 
Remarks.—It may be questioned whether heterospory is a sufficiently im- 
portant character to act as a specific index by itself. I am, however, 
inclined to maintain Binney’s species chiefly on the grounds of convenience. 
Type. No. 471, Carbon. Plant Coll, Sedgwick Museum, Cambridge. 
Also 472 (Lepidostrobus ? dubius, Binney). 
Distribution. Lower and ? Middle Coal Measures. 
Lower Coal Measures :— Blackband lronstone near Airdrie, Lanark- 
shire. 
Middle Coal Measures :— Thick Coal, Chilvers Coton, Warwickshire. 
Subgenus ORTHOLEPIDOSTROBUS, n. n. 
LEPIDOSTROBUS BREVIFOLIUS (Lesq.). (Pl. 8. figs. 4, 5, 6, 7, 8.) 
Sporophylls detached. 
1858. Lepidophyllum brevifolium, Lesq., in Rogers, Geol. Pennsyl. vol. ii, pt. 2, p. 876, 
pl. 17. fig. 6. 
1879-80. Lepidophyllum brevifolium, Lesq., Coal Flora Pennsyl. p. 447, pl. 69. fig. 33. 
1888. Lepidophyllum sp., Kidston, in Trans. Roy. Soc. Edinb, vol. xxxiii. pt. 9, 
p. 995, pl. 27. figs. 7 a, 7 b. 
1912. Lepidophyllum brevifolium, Arber, Phil. Trans. Roy. Soc. ser. B, vol. ceii. p. 252. 
Diagnosis. — Sporophylls small, up to 1*8 em. in length and 7-12 mm. across 
at the greatest width. Pedicel extremely narrow, keeled, very elongately 
wedge-shaped, about 8-10 mm. long. Lamina shortly triangular, often 
nearly equilateral, lower angles somewhat incurved towards the pedicel, 
about 7 to 12 mm. broad at the base, which is usually the broadest part. 
Remarks.—The sporophylls of this species are, with exception of the speci- 
men figured here, not yet known attached to the cone axis. 
No. 1249. The specimen figured on PI. 8. fig. 4, natural size, and enlarged 
twice on Pl. 8. fig. 5, is a medium-sized example of a detached sporophyll. 
The whole length of the pedicel is probably not disclosed. The region has a 
distinct keel. 
No. 1250. Another not very perfect specimen is shown on Pl. 8. fig. 7, 
natural size. The pedicel here has a broad expansion on either side of the 
keel, and this may possibly be a fluttened sporangium. 
No. 1257. One of the largest examples known to me is shown natural size 
on Pl. 8. fig. 8. This sporophyll exceeds 17 mm. in length and 10 mm. in 
breadth. What appear to be traces of a sporangium are seen around the 
keel of the pedicel. 
No. 1266. On PI. 8. fig. 6 a specimen is shown natural size in which 
several sporophylls appear to be attached to an axis. The impression, how- 
ever, is not very clear, and the laminas are alone distinctly seen. 
