524 DR. NEWELL ARBER AND MR. F. W. LAWFIELD ON THE 
1910. Calamites varians, Renier, Doc. Étude Pal. Terr. houil. p. 17, pl. 45. 
1911. Calamites verticillatus, Jongmans, Anleit. Destimm. Karbonpfl. West-Europas, 
vol. i. p. 61, fig. 67. 
1912. ? Calamites (Calamitina) varians var. insignis, Johnstone, Mem. and Proc. 
Manchester Lit. and Phil. Soc. vol. lvi. No. 17, pl. 
1915. Calamites verticillatus, Kidston & Jongmans, Mededeel. Rijksopspor. Delfstoff. 
No. 7, p. 71, pl. 51. ? fig. 2 ; pl. 52. ? figs, 8-0, 6 & 7; pl. 156, fig. 7. 
DiaGnosis.—IJnternodes of variable length, strongly striated longitudi- 
nally. Striations more or less salient. Branch scars medium to large, 
circular, elliptic or quadrate, approximated, with a small umbilicus slightly 
eccentric. Leaf scars small rounded, quadrate, chain-like, approximated. 
DESCRIPTION OF SPECIMEN.—The example figured on PI. 24. fig. 18, natural 
size, shows a number of internodes and a branch-bearing node. The nedes 
are distinetly tumid and the internodes are strongly ridged longitudinally ; 
between the ridges are finer parallel striae. 
Distribution. 
Middle Coal Measures—rare. 
Yorkshire ; Notts, and Derby. 
Lower Coal Measures. 
Ayrshire. 
CALAMOPHLOIOS SUCKOWI, Arber. (Plate 24. figs. 11-12; Plate 25. 
fig. 21.) 
1915. Calamites Suckowi, Kidston & Jongmans, Mededeel. Rijksopspor. Delfstoff, No. 
p. 111, pl. 8b. fig. 2. 
DraaNosts.—ZJnternodes usually broader than long. Surface smooth, with 
sub-cortical striations. Branch scars absent or very rare. Leaf scars small, 
distant, obscure. 
DESCRIPTION OF SPECIMENS.—The specimen figured on P1.24. fig. 11, natural 
size, appears to be the termination of a branch or rhizome. In the upper 
part the characteristic pith cast of C. Suckowi is seen, while below two 
internodes, showing external surface, are visible. The surface of these 
internodes is quite smooth, but there are longitudinal wrinkles and a very 
faint longitudinal and probably sub-cortical striation can be observed. Leaf 
scars are small, distant and indistinct. 
Another specimen probably belonging to this species is figured on Pl. 25. 
fig. 21, natural size. This shows four nodes, separated by smooth internodes 
which are, however, very faintly striated longitudinally. The leat scars are 
again indistinct. 
Another fragment, similar to that first described, is seen on Pl. 94. fig. 12, 
somewhat enlarged. On the left-hand side the external features of the 
internodes are seen, while on the right the pith cast is exposed, 
