January 19, 191 1] 



NATURE 



387 



The valuable series of memoirs on water supply is con- 

 tinued by one on Oxfordshire, by Mr. R. H. Tiddeman 

 (1910, price 25. 3d. J, and one on Hampshire and the Isle of 

 Wight, by Mr. \V. Whitaker (1910, price 5s.). Dr. H. R. 

 Mill contributes the chapters on the rainfall of the areas. 



The Survey's " Summary of Progress " for 1909 (1910, 

 price 15.) contains, as usual, a record of new observations, 

 of which further details may be expected later. .\ number 

 of Devonian inliers have been found in the Culm-measure 

 area west of Dartmoor. Mr. Clement Reid is prepared to 

 correlate the well-known Bovey beds, with which even 

 Playfair was acquainted, with the lignites of the Rhine, 

 j and to assign them to the Upper Oligocene. They thus 

 I fill a gap in British geology above the Hamstead beds 

 of the Hampshire basin. " The Bovey flora . . . seems 

 ! to be essentially the flora of the granite-ravines, with the 

 I admixture of a very few aquatic forms. . . . Marsh-plants 

 i are exceedingly rare " Cp- 18). The additions to our 

 i knowledge of the Isle of Mull are conspicuous (pp. 26-38). 

 i Upper Lias and Middle Jurassic beds have now been dis- 

 covered on Loch Don, thus filling part of the gap that 

 1 occurs at Carsaig between the representatives of the 

 j Jurassic and the Cretaceous (see also p. 57). " Corn- 

 ] stones " in the Trias of Morvern (p. 35) indicate arid 

 conditions; and Mr. Maufe's tropical experiences are here 

 used to advantage. Detailed analyses of Devonshire clays, 

 derived from granite, are given on p. 59. The titanium 

 dioxide is usually more than i per cent., while zirconia 

 and vanadium sesquioxide are each about 0-03 per cent. 

 Mr. L. Richardson contributes an elaborate and well- 

 illustrated paper on " The Inferior Oolite and contiguous 

 Deposits of the South Cotteswolds " to the Proceedings 

 of the Cotteswold Naturalists' Field Club, vol. xvii., 1910, 

 p. 63. He also discusses some of the hollows on the 

 Cotteswold scarp in a paper on glacial features (ibid., 

 p. 40), and shows how the Ice age has probably left its 

 traces in the land-forms here, as in North Wales. Mr. 

 Richardson read his paper in 1909, and about the same 

 time Prof. W. M. Davis, to whose work on Snowdon he 

 refers, contributed a short paper on " The Valleys of the 

 Cotswold Hills " to the Proceedings of the Geologists' 

 Association (vol. xxi., p. 150). He points out that " when 

 the curves of a stream are too small for the curves of its 

 valley, a diminution of stream volume is to be inferred." 

 The Evenlode and other valleys on the back of the Cottes- 

 wolds are too large for their present streams, and this 

 may be due to their beheading by the recession of the 

 escarpment. But the author suggests that they may 

 formerly have been occupied by water escaping from small 

 lakes between an ice-front in the Liassic lowland and the 

 face of the Cotteswold cuesta. Such water would select 

 the pre-glacial valleys, and would enlarge them. 



In tlie same journal (vol. xxi., p. 333) Messrs. C. R. 

 Bower and J. R. Farmery add to our knowledge of "The 

 Zones of the Lower Chalk of Lincolnshire," working up- 

 wards from the top of the Red Chalk or Hunstanton 

 Limestone. They see cause to differ as to the selection 

 of zone-fossils made by previous writers, and choose, going 

 upwards, Holaster suhglobosus, Terebratulina ornata, and 

 Holasier trecensis. Forty-three species are added to the 

 records from these beds, and a plate is given to show the 

 range of form in Discoidea cylindrica, from a pentagonal 

 type in the lower zone to a flattened one, with a circular 

 base, in the upper zone. Messrs. J. G. Hamling and 

 T. Rogers [ibid., iqio, p. 451) furnish a new coloured 

 geological map of North Devon, on the scale of three- 

 quarters of an inch to one mile. 



In the same volume of the Proceedings of the Geolc^ists' 

 -Association, p. 489. Mr. M. A. C. Hinton summarises his 

 work on the British fossil voles and lemmings, and makes 

 some very interesting remarks on the climatic conditions 

 accompanying the maximum extension of ice in our 

 islands. He regards the "Great Ice Age" in Britain as 

 due to " glaciers formed in the mountainous districts," 

 though it is not clear whv Britain in this respect should 

 differ so widely from Ireland or Scandinavia. His views 

 are in happy agreement with those of Dr. Scharff as to the 

 survival of Lusitanian members of our fauna through the 

 alleged destructive epoch of maximum glaciation. 



R. F. Scharff (Proc. Royal Irish Academy, vol. 

 sect. B, No. I, price 15.) writes on " The 



Or 



^xvin., sect. B, No. i, price 15.) 

 x\0. 2 15 I, VOL. 85] 



Evidences of a Former Land-bridge between Northern 

 Europe and North America." His paper has a speciaL 

 bearing on the origin of the present flora and fauna of 

 Ireland. The author holds that land-bridges afford the 

 only means by which terrestrial species are permanently 

 transferred to a new habitat. He makes out a good case 

 for the existence of a connection between our islands and. 

 .America in late Pliocene times, and for the pre-GlaciaL 

 origin of our flora and fauna. Incidentally, there is much 

 that will interest workers on glacial climate, though the 

 view (p. 5) that " the Glacial period was primarily due 

 to the diversion of oceanic currents " will not explain the 

 simultaneous glaciation of Europe, North America, and. 

 the central .Andes. The only way out of this difficulty, 

 if we rely on ocean-currents, is to accept, with M. Stanislas- 

 Meunier (Revue des Idees, September 15, 1910, p. 2i9)» 

 the still more difficult proposition that post-Pliocene glacial 

 phenomena were separated, in various regions, by intervals- 

 of several thousands of years. 



The Transactions of the Hull Geological Society for 

 1906-9 (1910, price 25. 6d.) show how local observation 

 ma\- be aptly stimulated. Mr. Sheppard most usefully 

 summarises, with numerous illustrations, recent publica- 

 tions bearing on the district. Mr. F. M. Burton has 

 issued a paper on " The Witham and the .Ancaster 

 ' Gap ' " as a separate publication (London and Hull : 

 Brown and Sons, price i5.). Surely this would have found 

 better circulation through one of the northern scientific 

 journals. Something seems omitted in a critical passage , 

 on p. 12, W'here the " clays of the Upper Lias and beds 

 of Marlstone " are said to have extended eastwards,. 

 " cuttfng through the Lower Oolite at Ancaster, and form- 

 ing the ' Gap ' there." 



In the Quarterly Journal of the Geological Society of 

 London, vol. Ixvi., part iii-, issued in .August, 1910, Mr. 

 L. Moysey discusses (p. 329) Brongniart's genus 

 Palaeoxyris, as abundantly revealed in the Derbyshire and 

 Nottinghamshire coalfield. The similarly problematic 

 organisms Vetacapsula and Fayolia are also found, the 

 former being known only from England. All three genera 

 are believed by the author to be egg-cases of fishes. The 

 society, as is well known, publishes abstracts of the dis- 

 cussions on its papers, a practice that should be universally 

 followed under careful editing. We gather that the types. 

 of fish that would produce such egg-cases are practically 

 absent from the beds where the three genera are found, 

 and that botanists may still rise up to claim these quaint 

 elongated bodies. 



Miss H. Drew and Miss T. Slater (ibid., p. 402) describe 

 the " Geology of the District around Llansawel (Car- 

 marthenshire)," where little has been done since Sedgwick 

 wrote in 1854. The beds described are Gotlandian, and 

 include the whole Birkhill series, followed by Lower Gala 

 beds. 



Mr. T. O. Bosworth's work on the metamorphism 

 round the Ross of Mull granite is referred to in the 

 Summary of Progress of the Geological Survey for 1909. 

 He now (Quart. Journ. Geol. Soc, 1910, p. 376) describes 

 the beautiful phenomena of injection of granite along the 

 foliation-flexures and other planes of weakness in the 

 surrounding garnetiferous mica-schists. The latter belong 

 to the Moine series of the Highlands- Groups of well- 

 bounded prisms of sillimanite occur as contact-products in 

 the schists, in addition to the ordinary fibrolitic type. 

 There are some indications in the long and interesting 

 discussion that the views of many Continental observers 

 as to the potency of metamorphism by injection are 

 spreading among workers in the British Isles. 



Mr. G. W. ^Tyrrell, of Glasgow University, has pub- 

 lished several papers on the characters of igneous rocks 

 in southern Scotland. Writing on the " Intrusions of the 

 Kilsyth-Croy District, Dumbartonshire " (Geological] 

 Magazine, 1909, pp. 299 and 359), he points out that the 

 feeders of the laccolite of diabase in this district " appear 

 to cut " the Linlithgowshire intrusive rocks, which have 

 been regarded as of Cainozoic age. Since there is much 

 evidence that the Kilsyth Croy rocks are of post-Carbon- 

 iferous, but still Palaeozoic, date, the Linlithgowshire 

 series to the south must also be late Palaeozoic. Micro- 

 pegmatite veins occur through the diabases, and give cause 

 for an interesting discussion (p. 362) as to their origin in- 



