^{page 409 note *} Links from other quarters, having been subsequently added to his formation-suites, by his pupils.

^{page 410 note *} Greenstone is a literal translation from the German; it is an extremely improper name; but as we have no other by which we can distinguish this variety of trap, we must use it till a more appropriate is found, even at the expence of such language as red and blue greenstones. In the mean time, it must be understood merely as an arbitrary term.

^{page 413 note *} One of the greatest difficulties which geology as well as mineralogy has laboured under, is the multitude of synonymous terms which have been applied to every individual fossil. Trap has suffered from this disadvantage, perhaps more than any other variety of rocks; as above noticed, that name is derived from the similarity to the steps of a stair, which may generally be traced in the outline of a country, in which this rock abounds; and as it has been employed as a generic term by mineralogists throughout Europe, I think it proper to use it, to the exclusion of whinstone, the name it bears in the writings of Dr Hutton; a name which, though perfectly understood in this country, is not received abroad, and ought therefore to be relinquished.

^{page 418 note *} The term dyke has been very generally applied to veins of this description, and I am not satisfied that it is the least proper of the two; as there certainly is a marked distinction between veins composed of rocks, and what we generally understand by mineral veins. The first are formed of one uniform rock, composed in all their parts of the same constituents, and differing only in position, from the beds these materials more usually form; while the latter, though sometimes formed only of one substance, such as quartz or calcareous spar, are generally composed of a series of fossils, arranged in lines parallel to the walls. No such appearance ever prevails in rock veins, or constituting mountain masses; therefore, in using the term vein, when applied to greenstone, granite, or the like, it must be understood as a generic term, of which these latter, specify the variety.

^{page 420 note *} Corresponding numbers will be found in the annexed engraving, which will explain, more fully the relative position of the specimens.

^{page 422 note *} Illustrations of the Huttonian Theory, § 68.

^{page 423 note *} Since this paper was sent to press, others have been observed in different parts of the rock.

^{page 425 note *} By junction specimen is meant, a specimen which exhibits the greenstone. and the sandstone conjoined.

^{page 427 note *} Comparative View of the Huttonian and Neptunian Theory, p. 130.

^{page 427 note †} System of Mineralogy, vol. iii p. 365.