NOTES AND QUERIES. 39

Observations on the Terms " Permeen," " " and " Dyas." By Jules Marcou. Boston. 1862. These " Observations " have been reprinted by M. Jules Marcou, from the Proceedings of the Boston Society of Natural History, in which he refers directly to the artiyle by Sir Roderick Murchison, printed in the last year's January number of this magazine, and gives a list of dates in respect to the priority of the term " Permian." M. Marcou also refers to his own memoir, " Dyas and Trias," in the ' Archives do la Bibliotheque Universelle de Geneve,' 1859, as treating the two questions entirely distinct. Since the first publication of M. Mar- cou's paper, M. Ludwig, one of the associates of Dr. Geinitz, has been to Russia, and has published the results of his researches, under the title ' Geogenische und geognostischo Studien auf einer Reise durch Russland und den Ural.' We have not yet seen this work, and therefore cannot say of our own knowledge whether it docs or does not bear out M. Marcou's statement that it gives ample facts and sections to show " the inapplicability of the term ' Permian' to the Dyas of Saxony; a term which indeed would not have been for a moment maintained if its typical localities were in a more accessible part of the world." M. Marcou next considers the necessity of the union of Dyas and Trias into a great geological period—the New Red Sandstone. This period he considers in time and space to be of the same importance as the Grauwacke or Paleozoic, , Secondary, Tertiary, and Recent periods. He has never admitted tlie union of the Now Red Sandstone with the Carbo­ niferous or the Secondary.

Etude sur I'Etaqc Kimmiridien dans les Environs de Montheliard. By Dr. Cii. Contejean. Leipzig: J. Rothschild. 1860. Acting on the recognized principle of marking geological periods by particular palajontological fauna;, Dr. Contejean has set about to deter­ mine the boundaries and members of the Kimmeridian formation of Montbeliard, and in the Jura, , and England. To the want of due regard to palasontological evidences, and the too great importance attached to pctrographical facies, Dr. Contejean attributes the great number of purely artificial divisions—the limitation of the systematizing of the beds being thus restricted to the mere differences of mineral composition, with­ out due regard to palscontological horizons. In the Jura, the massive "Astarte, Pterocera, and "Virgula marls" are ordinarily taken as the base of the Kimmcridge group ; upon these are superimposed directly thick in­ termediate limestones, often sterile or but slightly fossiliferous, These divisions may be strictly conformable to subpelagic regions, where the marly beds alone received the organic debris. " But," well asks Dr. Contejean, " are these good divisions in themselves, and can they be applied more generally ?" This question he answers in the negative, and cites the very rich fossiliferous localities of Montbeliard and Ponentruy as evidence. In those regions, formerly littoral, the limestone strata which separate the marls have received the relics of faunas hitherto not appre­ ciated, but which are of equal value with those of the marls, and conse­ quently entitled to rank as independent sub-groups. Moreover, the faunas of certain marl horizons are in no wise different from those of the limestones in their respective vicinities; and thus the natural limits of the divisions are not always restricted either to the base or to the surface of a marl-bed; whilst some limestones belong to two, or even three, different 40 THE GEOLOGIST.

divisions, and therefore if there exist three chief divisions in the Kimme- ridien formation, the limits of these groups are very different from those which have been assigned to them. These are the opinions Dr. Contejean has striven to work out in the book before us, and to this end he first describes the geographical range of the Kimmeridge beds, through Damvant, Abbevillers, Audincourt, Mont- beliard, and Belfort, in a north-westerly direction ; then through the Allan Valley to the district of Ponentruy ; and next, south-westwards, toLong- velle and ITle-sur-le-Doubs. He then describes the subdivisions, with their mineral characters and their characteristic fossils. These .subdivisions are :—-(1) Calcaire a Astartes; (2) Caleaire a Naliccs; (3) Marries a Astartes ; (4) Calcaires a Terebratules ; (5) Calcaire a Cardium ; (6) Cal- caires et Marnes a Pteroceres; (7) Calcaire a Covins; (8) Calcaires a Jifactres ; (9) Calcaires et Marnes a Yirgules ; (10) Calcaire a Diceras. A section of his book is now devoted to detailed lists of the respective faunas of each of these subdivisions, and to comments upon them. After a summary of the facts thus brought forward, he tabulates his results in the following manner :— ETAGE KIMMERIDIEN. IV. Groupe NEEINEEN . Subdivisions to be made out. lO. s. gr. Calcaire a Diceras. 9. Calcaires et Marnes a Viryulcs. 8. Calcaire a Mactres. i 7. Calcaire a Corbis. f 6. Calcaires et Marnes a Pte'roceras. II. Groupe PTEBOCEBIEN 5. Calcaire a Cardium. I 4. Calcaire a Terebratules. f 3. Marnes a Astartes. I. Groupe ASTAETIEN . I 2. Calcaire a Natices. { 1. Calcaire a. Astartes. The last question then remains—w'hat are the limits of the Kimmcridien as thus defined? These Dr. Contejean asserts are exactly indicated. The Kimmeridge division terminates the marine series, and is naturally arrested by the Purbeck beds, which most geologists have considered , but which the author considers M. Coquand has rightly asso­ ciated with the Jurassic formation. The inferior limits he sets forth as equally easy to establish, the Kimmeridge division commencing where the mass of fossil corals ends, or immediately above the Diceras beds of the Coralline Oolite. The fourth section of his work Dr. Contejean devotes to the " Parallel­ ism of the Formation," and notices the characters presented in the Medi­ terranean basin, Straits of Dijon, Anglo-Pari si an basin, and the Pyrenean basin. This is followed by a fifth portion, with geological sections and a general list of the fossils of the whole formation. The remainder of the book, amounting to a hundred pages, is taken up with detailed descriptions of new or critical species of shells, w hich are illustrated by twenty-four ad­ mirable lithographed plates, very carefully and accurately drawn. The book is moreover illustrated by three plates of sections and stratigraphical diagrams of the ranges of the various groups of fossils. We have, in former reviews, had occasion to speak well of the geological works published by M. Rothschild, but of none we have yet noticed could we desire to speak in higher terms of praise than of Dr. Contejean's admi­ rable monograph before us.