Dec. 14, 1871] 



NATURE 



121 



OUR BOOK SHELF 



RuJi/i!c->itary Treatise on Geology. — Part H. Historical 

 Geology. By Ralph Tate, A.L.S., F.G.S., &c. With 

 Illustrations and an Index. (London ; Lockwood and 

 Co.) 

 This little book is partly based on Portlock's " Rudiments 

 of Geology," and " is set forth in the full belief that it 

 will be found to be an epitome of the history of the British 

 Stratified Rocks." The first three chapters are introduc- 

 tory, and contain the usual table of the British Sedimen- 

 tary Strata, with some brief remarks thereon, which are 

 followed by what the author calls a " Pateontological 

 Summary." In this summary he takes a rapid view of 

 the animal and vegetable kingdoms, and points out briefly 

 under which classes and orders fossil organic remains 

 may be ranged. The rest of the volume is entirely occu- 

 pied with descriptions of the Formations and their sub- 

 divisions, and with lists of characteristic fossils. We have 

 no doubt that the preparation of this book has cost its 

 compiler considerable labour ; and he certainly has 

 managed to cram a good deal into the short space at his 

 command. The information, indeed, is just too tightly 

 packed ; it forms very dry reading, and will be apt to 

 frighten a beginner. If it was necessary that the volume 

 should be no larger than it is, we think some of the paL-c- 

 ontological details might have been omitted, and here and 

 there the description of minor subdivisions of formations 

 conveniently cut even shorter than they are, so as to ob- 

 tain room for certain particulars about the history of the 

 strata, which are either too meagrely noticed or are alto- 

 gether ignored. The references to former volcanic action 

 in Britain are quite inadequate. We find no mention of the 

 fact that volcanoes were active in the South-West of 

 England during the deposition of the Devonian Strata ; 

 nor is there any notice taken of the occurrence of volcanic 

 rocks in the Old Red Sandstone of Ireland. A slight 

 allusion is made to the igneous rocks of the Scottish 

 Middle Old Red Sandstone, but the far more extensive 

 volcanic products belonging to the Lower Old Red series 

 are passed over altogether. The igneous rocks of the 

 Pentland Hills are not, as the author states, of " Upper," 

 but of Lower Old Red Sandstone age. Again the 

 reader, looking over what is said about the igneous rocks 

 of Carboniferous age, would never learn that volcanoes 

 played so active a part in Scotland during the accumula- 

 tion of the Lower Carboniferous and Carboniferous Lime- 

 stone periods ; nor that in Ireland also volcanoes here 

 and there piled up ejectamenta upon the bed of the Car- 

 boniferous Limestone sea. Surely in a book purporting 

 to be an epitome of the history of British stratified 

 rocks, the volcanic phenomena that characterise so many 

 successive epochs of the past ought to have had a some- 

 what fuller notice. There are various other points in con- 

 nection with physical geology which are quite ignored. 

 For instance we find no mention of Prof. Ramsay's theory 

 of the Glacial origin of certain breccias and conglomer- 

 ates of Silurian, Old Red Sandstone, and Permian age — 

 a theory which, whether Mr. Tate agrees with the Professor 

 or not, ought certainly to have had some reference made 

 to it no matter how brief. We had marked a number of 

 passages where the author's meaning is not very clear and 

 will be apt to puzzle a learner. One of these will suffice. 

 Speaking of the Glacial epoch, the author says :— " Our 

 inquiry has now come to that point where, though we 

 still see in the recent results of geological phenomena 

 evidence of the formative processes of nature, yet we are 

 kept at a distance from the present epoch ; for although 

 the shells are all of living species, they are generally 

 arranged in positions and associated with detrital matters 

 of such a description that their appearance indicates the 

 action of forces prior to the present order of things." 

 Occasionally we come across statements which are very 

 far from being consistent " with the opinions generally 



held by geologists." We read, for instance, that "the 

 first trace of a land plant is at the very top of the Upper 

 Silurian, and we may conclude that there were no terres- 

 trial plants during the long Silurian epoch, a vast interval 

 far exceeding in duration that of any other system." 



Besides figures of characteristic fossils, the volume is 

 illustrated with a number of diagrammatic sections. A 

 copious index is appended. J. G. 



Illustrated Catalogue of the Museum of Comparative 

 Zoology at Harvard College. No. IV. Deep-sea 

 Corals. By L. F. de Pourtales, Assistant U.S. Coast 

 Survey. 1871. 

 Count Pourtales had the good fortune to be one of 

 that band of naturalists who, dredging for the first time in 

 deep water between Key West and Havana, came to the 

 conclusion that " animal life exists at great depths in as 

 great an abundance as in shallow water." This opinion 

 was published in his " Contributions to the Fauna of the 

 Gulf Stream at great Depths" (Cambridge, U.S., 1867). 

 Moreover as a zoophytologist he had the credit of 

 obtaining the first true stony corals from great depths. 

 Numerous corals were dredged up under his superintend- 

 ence in 1 868 and 1S69 from oft" the sea floor of the so- 

 called Straits of Florida in the course of the Gulf Stream, 

 and they were carefully described by him in Nos. 6 and 7 

 of the last-mentioned work. Now the results of the Deep- 

 sea Dredging so far as the Corals are concerned, appear 

 in the handsome essay in quarto before us ; the specific 

 descriptions have been revised, new forms are described, 

 and the illustrations in lithography testify to the excel- 

 lence of American printing from stone. The interesting 

 coral fauna in the deep sea of Florida has already to a 

 certain extent been compared with that of the cold and 

 warm area of the North Atlantic, in the Proceedings of 

 the Royal Society, March 24, 1870 ; and the new species 

 described by M. de Pourtales, together with the remarks 

 upon the classification of the corals, will probably enhance 

 the importance of the labours of those English naturalists 

 who have undertaken the description of the results of 

 our abyssal dredgings. The great horizontal range of 

 some of the deep-sea corals is as remarkable as the ver- 

 tical range of others ; and M. de Pourtales, although 

 strongly impressed with the importance of some struc- 

 tural characters in the distinction of specific differences 

 which are not thought so valuable and important in 

 England, leans to the belief in these ranges. The Ameri- 

 can deep-sea coral fauna is not so rich in species, and 

 apparently in individuals, as that of the North Atlantic 

 and Lusitanian Coasts, but there is one form which is 

 found in the globigerina mud off BahiaHonda, Florida, 

 in 324 fathoms, which will always be of interest to the 

 naturalist who studies palaeontology. Haplophyllia par- 

 adoxa Pourtales, possesses all the essential characters of 

 the Rugosa, and is allied to the simple coral, Calophyl- 

 luiii profundujii Germar — the Permian Polyca'lta pro- 

 funda of King, but it has been shown to be also allied to 

 Cuynia annulata Duncan, a small rugose coral dredged 

 off the Adventure Bank in the Mediterranean. Both Hap- 

 loph.yllia and Guynia have a strong central axis or colu- 

 mella, the existence of which is of generic importance, 

 and it is therefore necessary to ally these two modern re- 

 presentatives of the old Rugosa which dominated in the 

 coral fauna of the Pakeozoic age with the Cyathaxonidae 

 of the Carboniferous rocks. M. de Pourtales is so gentle 

 a critic that if one wished to differ from him in print, the 

 desire would fail. When the Zoological Society print, 

 which they are about to do, the Essay on the deep-sea 

 corals dredged from H.M.S. Porcupine, nothing will be 

 more satisfactory than that an interchange of notes and 

 specimens should take place, so that in a supplement the 

 American and English authors may terminate their un- 

 important little dift'erences in classification. The beauty 

 and correctness of the illustrations are extreme, and they 

 do the artist, and especially the printer, great credit. It 



