NOTES AND QUERTES. 



30 



Observations on the Terms " Permeen" " Permian" 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 article by Sir Eoderick 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 de la Bibliotheque Universelle de Geneve,' 1859, as treating the 

 two questions entirely distinct. Since the first publication of M. Afar- 

 cou's paper, Iff. 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 geognostische Studien auf einer Peise durch Bussland 

 und den Ural.' We have not yet seen this work, and therefore cannot 

 say of our own knowledge whether it does 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 Ped Sandstone. This period he 

 considers in time and space to be of the same importance as the Grauwacke 

 or Palaeozoic, Carboniferous. Secondary. Tertiary, and Eecent periods. He 

 has never admitted the union of the New Eed Sandstone with the Carbo- 

 niferous or the Secondary. 



Etude sur VEtaqe K'nnnuridien dans les Eiwirons de Montbeliard. By 

 Dr. Cii. Contejean. Leipzig : J. Pothschild. 1860. 



Acting on the recognized principle of marking geological periods by 

 particular pala?ontological fauna?, Dr. Contejean has set about to deter- 

 mine the boundaries and members of the Ximmeridian formation of 

 Montbeliard, and in the Jura, France, and England. To the want of due 

 regard to pala?ontological evidences, and the too great importance attached 

 to petrographical 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 palaeontological horizons. In the Jura, the massive 

 u A st arte, Pterocera, and Yirgula marls" are ordinarily taken as the base 

 of the Kimmeridge 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 



