and some other Stratified Deposits in the North of Scotland. 299 



oolitic formation in the vicinity of Whitby, appear to me distinct fiom any 

 which are known to occur in the true coal-formation. Most of these plants 

 are undescribed, and deserve to be characterized from more perfect specimens 

 than those before me. 



" In most of the fragments of the slate-clay which I have seen, two or three 

 distinct plants, or rather parts of plants, might be distinguished. One of these 

 appears either in the shape of carbonaceous expansions exhibiting acute 

 regular furrows of various lengths, gradually diminishing in width, and run- 

 ning out into linear grooves ; the intermediate space, in the more perfect spe- 

 cimens, being marked with depressed dots ; or in the shape of elevated rays 

 or ribs having a pretty acute ridge and gradually tapering, from the width of 

 -^ of an inch, into a fine, more or less lengthened, raised line. The latter 

 appearance is produced by a counter-impression from the grooved expan- 

 sions. Together with these are seen well defined composite leaves : they are 

 bipinnated, with pinnatifid ovate leaflets, having veins proceeding from the 

 base, without a distinct mid-rib. They might, on account of their regular juxta- 

 position, be considered as having belonged to the abovementioned grooved 

 and radiated expansions, could not the origin of these latter be traced to an 

 order of plants which does not seem to admit of such a foliation ; I mean, the 

 arundinaceous vegetables found in the sandstone above the slate-clay. These 

 consist of portions of jointed stems from one to two inches in diameter, and 

 of various length ; they are either cylindrical or collapsed and flattened; their 

 joints, from one to three inches distant from each other, appear as bulging 

 rings, and, if broken at the places of junction, exhibit traces of a dissepiment 

 which also appears to be indicated in some specimens by a slight depression 

 round the middle of the projecting ring. The surface of the cylindrical frag- 

 ments is nearly smooth and even ; but at some distance from the joints fine 

 grooves appear, which are widest near and on the tubercular swelling, where 

 they assume the form of equidistant narrow slits, each formed by two planes 

 meeting under a rather obtuse re-entering angle. Above the articulations, in 

 some specimens, may be observed traces of a single impression or cicatrix; 

 those which are not furnished with this may possibly belong to the root of 

 the vegetable. 



''Now, on comparing many of the grooved joints of these reeds in the sand- 

 stone with the ribbed leaf-like expansions in the shale, it will be found that 

 there is no difference between them, except that in the former, though re- 

 duced to a thin film of coal, the shape of the stem has been more or less pre^ 

 served by the hardened sand in their interior; while in the latter the carbo- 



