o/' Ulodendron to Lepidodendron, &c. 165 



leaf-scar, but. its details of structure are not shown. The 

 leaf-scars are almost contiguous, being only separated laterally 

 from each other by the caudate extension, which runs from 

 the apex of one scar to the base of another. The bark is 

 much cleft by longitudinal fissures ; a portion of one of these 

 is shown in the figure. The matrix on which the impression 

 has been stamped is a very fine bituminous oil shale. 



This example also shows at certain parts the same charac- 

 ter, though not so strongly carried out, as in the specimen of 

 Lepidodendron acuminatum mentioned by Stur, Culm- Flora, 

 p. 398, pi. xxii. (xxxix.) fig. 4, where the leaf-scars some- 

 times seem to lose their spiral arrangement, and appear to 

 be placed in vertical rows, simulating somewhat in this pecu- 

 liarity a sigillarian arrangement of leaf-scars. 



Specimen No. 6. From Blackbraes, West Calder, Mid- 

 lothian (Oalciferous Sandstone Series). Collected by J. Linn, 

 Esq. PI. VI. fig. 11. — The specimen, shown in fig. 11 

 reduced to ^ natural size, measures in its greatest length 7 

 inches, its width being about 4 inches. The fossil shows part 

 of a stem, which must have been of considerable size. The 

 small fragment of it ihat has been collected^ still retains its 

 rounded form, and seems to have suffered little from pressure. 

 The matrix of this example is a fine-grained sandstone, and 

 fhougli the leaf-scars are not very well shown, at a, fig. 11, 

 they are sufficiently well preserved to admit of a satisfactory 

 specific determination. The Ulodendroid scar is almost cir- 

 cular, considerably depressed, and measures about 1^ inches 

 in diameter. The basal portion of the appendicular organ 

 which fits into the scar has also fortunately been preserved. 

 This is shown in profile at fig. 11 b, and a view of its basal 

 aspect is seen at fig. lie; both of these figures are natural 

 size. The outer surface of the fossil is discoloured by the 

 carbonaceous matter of the plant. This is especially marked 

 on the surface of the depressed Ulodendroid scar^ and on the 

 base of the appendicular organ, which, with the exception of 

 a very small spot towards the centre of each, indicating 

 the point of attachment of the appendicular organ, are 

 stained dark brown. Had the appendicular organ been 

 attached to the stem by the whole of its surface, its base and 

 the surface of tlie Ulodendroid scar could not have been 

 covered with carbonaceous matter. To the right of fig. lie 

 are seen in the matrix what may possibly be the remains of 

 leaves, in the profile, fig. 11 b, the markings on the outer 

 surface of the appendicular organ have very much the appear- 

 ance of leaf-scars, but cones, when the upward extending 

 portion of their bracts is broken oft'^ have also a resem- 



