I owe to the kindness of Mr. Robertson, Inverugie, the specimen figured in Plate V., fig. 7, containing shells of the only species yet discovered in the Old Red Sandstone of Scotland. They occur in the Lower Formation of the system, in a quarry near Kirkwald, in which the specimen figured, with several others of the same kind, was found by Mr. Robertson, in the year 1834. In referring to this shell, page 99,[B] I have spoken of it as a delicate bivalve, much resembling a Venus; drawing my illustration, naturally enough, when describing the shell of an ocean deposit, rather from among marine, than fluviatile testacea. I have since submitted it to Mr. Murchison, who has obligingly written me that he "can find no one to say more regarding it than that it is very like a _Cyclas_." He adds, however, that it must be an ocean production notwithstanding, seeing that all its contemporaries in England, Scotland, and Russia, whether shells or fish, are unequivocally marine. [Footnote B: Page 90 of the present edition.] With the exception of two of the figures in Plate IX., the figures of the _Cephalaspis_ and the _Holoptychius_, and one of the sections in the Frontispiece, section 2, all the prints of the volume are originals. To Mr. Daniel Alexander, of Edinburgh,--a gentleman, who to the skill and taste of the superior artist, adds no small portion of the knowledge of the practical geologist,--I am indebted for several of the drawings; that of fig. 2 in Plate V., fig. 1 in Plate VI., fig. 2 in Plate VIII., and figs. 3 and 4 in plate IX. I am indebted to another friend for fig. 1, in Plate VII. Whatever defects may be discovered in any of the others, must be attributed to the untaught efforts of the writer, all unfamiliar, hitherto, with the pencil, and with by much too little leisure to acquaint himself with it now. AMERICAN PUBLISHERS' NOTICE. The publishers take pleasure in presenting to the American reader this interesting work of Hugh Miller, in which are restored to our view some of the phenomena which occurred in the earlier formations of the crust of the earth, belonging to those inconceivably remote ages when living things first appeared;--a work so scientific, and yet so illustrated with familiar objects and scenes, as to be well understood by those little versed in Geology. The grand conclusions which the author deduces from apparently trifling circumstances that every one has noticed a hundred times, without being the wiser, illustrate the difference between the philosopher and the common observer; and the simple and pictorial style in which they are delineated renders the work peculiarly fascinating.