212 THE LATE DR. NEWELL ARBER: CRITICAL STUDIES 
pinnules are frequently lobed or divided into minor pinnules at the base. 
The cyclopteroid-like pinnules have a broader point of attachment and a 
more radiating nervation, partly arising directly from the rachis. The lateral 
nerves are more frequently dichotomised than in the minor pinnules, but 
possess a similar inclination and are also sinuous in their course. 
Distribution. 
The following issthe distribution of this species in Great Britain, so far 
as it is known to me :— 
Middle Coal Measures. 
Derbyshire Coalfield :—Top Hard Coal, Shipley Clay Pit, Derby. 
Yorkshire Coalfield :—Above Silkstone Coal, Bond’s Main Colliery, 
Derbyshire. Old Hards Coal, Hartley Bank Pit, Horbury, 
Yorks. Horizon uncertain, Barnsley, Yorks. 
Ingleton Coalfield :—W. of Ingleton. 
Denbighshire Coalfield :—Llag Hill near Wrexham. 
? Kent Coalfield. 
Devonshire. 
Lower Coal Measures. 
Northumberland Coalfield :—Horizon uncertain, Felling. 
3. NEUROPTERIS CALLOSA, Lesq. 
I turn now to another type, which I hope to be able to show here is quite 
distinct from N. obliqua, Brongn., but which has been confused with it, 
although it is of very much commoner occurrence than that species. This 
plant I believe to be the Neuropteris callosa of Lesquereux, a species which 
has already been doubtfully recorded by Dr. Kidston from three British 
coalfields. 
Synonymy of Neuropteris callosa, Lesquereux :— 
1879-80. Neuropteris callosa, Lesquereux, 2nd Geol. Surv. Pennsylv. p. P. 115, pl. 16. 
figs. 1-4 (? figs. 5-8). 
1909. Neuropteris obliqua, Arber, Quart. Journ. Geol. Soc. vol. lxv. p- 26, pl. 1. fig. 3. 
1911. Neuropteris obliqua, Kidston & Jongmans, Arch. Néerl. Sci. Exact. et Nat. ser. 3 B, 
vol. i, p. 25, pl. (unnumbered), fig. 3. 
Remarks on the Specimens previously figured. 
Lesquereux's type was diagnosed as follows :—“ Bipinnate ; ultimate 
pinnæ linear; leaflets alternate, sessile by a broad base, oblong or oval, 
obtuse ; veins flabellate from the base, strongly marked, slightly curved ; 
cyclopterid pinnules cordate at the point of attachment, unequilateral, 
polymorphous.” 
Of Lesquereux’s figures, pl. 16. figures 2-4, are the most characteristic. 
Two of these figures are reproduced in text-fig. 2, p. 213. The bluntly 
