,2<5<) 



NATURE 



[April 22, 1920 



along a smooth curve, part of which indicated changes 

 in the Plioceneand part in the Miocene. From this curve 

 certain deductions are drawn, namely : (i) The study 

 of living and fossil seeds can lead to accurate specific 

 determinations. (2) The study of fossil seeds is as 

 accurate a method of determining geological age as is 

 palaeontology, and the age indicated for the Reuverian 

 and Castle Eden floras is approximately correct. 

 (3) The destruction and supplanting of the Chinese- 

 North American exotic flora began about the Middle 

 Miocene, at the time when the great European and 

 Asiatic Alpine ranges attained their maximum uplift ; 

 but it was to these trans-continental barriers that 

 Clement Reid and the author attributed the exter- 

 mination of this flora. Therefore, the curve gives 

 strong and independent confirmation of the truth of 

 their theory, and is in accord with the findings of 

 stratigraphy and palaeontology. (4) The curve indi- 

 cates an incoming flora — the present flora of Western 

 Europe and, in part, of Central and Southern Europe 

 — which first appeared in the Miocene. Of this the 

 aquatic element is now chiefly circumpolar in distribu- 

 tion, whereas the drv-soil element mainly centres in 

 the Himalayas. (5) The incoming flora only in part 

 survived in Western Europe ; the destruction became 

 greater after the Middle Pliocene; the cause of this 

 is unknown. 



Cambridge. 

 Philosophical Society, February 2^.— Mr. C. T. R. 

 Wilson, president, in the chair.— Prof. Seward : The 

 origin of the vegetation of the land. A brief con- 

 sideration of questions raised by Dr. A. H. Church 

 in a recent memoir on " Thnlassiophyta and the Sub- 

 aerial Transmigration" (Oxford, igiq). "The be- 

 ginnings of botany are in the sea." Life evolved 

 from the ionised water of a continuous world-ocean 

 two miles in depth. The plankton epoch ; unicellular, 

 free-floating plants. The Benthic epoch was initiated 

 when portions of the earth's crust rose to within the 

 reach of light and plants were able to establish them- 

 selves on the ocean-floor. Development during the 

 Benthic epoch of complex anchored marine plants. 

 The epoch of the land flora began with the emergence 

 of areas of land and the transference of plants from 

 the hydrosphere to the atmosphere. 



Manchester. 



Literary and Philosophical Society, March 2. — Sir 

 Henry A. Miers, president, in the chair. — ^W. J. 

 Perry : The search for gold and pearls in Neolithic 

 times. Further research on the distributions of earlv 

 sites of civilisation and of the sources of gold and 

 pearls has produced a mass of evidence to substantiate 

 and enlarge the thesis of an earlier paper bv the 

 author on " Megalithic Monuments and Ancient Mines." 

 The evidence now suggests that not only mep^alitbic 

 monuments, but also early sites in general, marked the 

 settlements of seekers after gold and pearls, amber and 

 purple haviner also played their part In attracting 

 strangers. These settlements are mostly localised in 

 the basins of rivers containing gold or pearl-bearing 

 mussels, and the distribution man shows that the 

 earlv seekers for these objects did not allow much 

 to escape them. Further inquiry will be necessary in 

 order to determine the nrecise age when this search 

 bpgan: — C. L. Barnes: Einstein's theory of space and 

 time. 



Edinburgh. 



Royal Society, March i. — Prof. F. O. Bower, 

 president, in the chair.— Prof. J. C. Ewart : The 

 nestling feathers of birds. This paper embodied cer- 

 tain facts of observation in regard to the development 

 of nestling feathers which did not harmonise with 

 NO. 2634, VOL. 105] 



the view generally taken that feathers were originally 

 developed out of scales. Three facts of fundamental 

 importance should be borne in mind: (i) The geo- 

 logical record has hitherto told us nothing about the 

 evolution of feathers; (2) the embryological record 

 affords no evidence in support of the view that scales 

 grew longer and lighter and, after much spreading 

 and splitting, became feathers; and (3) the true 

 feathers of modern birds are, as a rule, derived from 

 small umbels consisting at the outset of barbs, which 

 result from the splitting of the intermediate layer of 

 cells of a simple dermic papilla similar to the papillae 

 of the tongue of ducks. A study of simple nestling 

 feathers (prepennae) leads one to believe that the 

 plumage of primeval birds consisted of umbels 

 (protoptiles) which diff'ered but little from the bundles 

 of hair found in the jerboa and certain other 

 mammals, or of umbels consisting of barbs armed 

 with barbules, as in the feathers forming the first 

 nestling coat of oenguins, or of feathers with prac- 

 tically all the structures now associated with true 

 feathers. In course of thre feathers of a different 

 tvpe were evolved, which, as they grew, pushed from 

 the skin, and for a time carried on their tips the 

 feathers of the first generation. The second kind of 

 feathers (mesootiles) are now well represented in 

 oenguins and in the emu, and a remnant is still 

 found in ducks and freese; whether the body of 

 ArchaeoDteryx was clothed with protoptiles or with 

 mesootiles or with nlumose feathers it is impossible 

 to say. When all the facts recently established bv a 

 studv of the development of feathers are dulv con- 

 sidered, there is no escape from the conclusion that 

 the wing-quills are only highly specialised nestling 

 feathers, and that it is' Inconceivable that the first 

 nestling feathers were formed out of scales.^Dr. 

 T. M'Lean Thompson : New stelar facts and their 

 hearinf^ on stelar theories for the ferns. In order to 

 know how the comnlicated vascular system^ of adult 

 ferns came into existence, knowledge of individual 

 development was necessary. This has_ now been 

 traced bv sections in a number of specially^ chosen 

 cases, and the results reconstructed into diagrams 

 showing the individual advance. This involves the 

 formation of a pith, inner phloem, inner endodermis, 

 and freauentlv, * in the early stages of development, 

 pockets of outer endodermis. These tissues are new- 

 creations within the vascular svstem formed by a static 

 change of quality of the elements from the growing 

 point. The solenostele and other higher forms of the 

 vascular svstem arise by further modification of the 

 structures thus acauired. This involves the formation 

 of gaps in the vascular system, through which the 

 pith and cortex, originally distinct, unite to form one 

 continuous tis«;ue. The ferns dealt with range from 

 the primitive Schizaeaceae to the advanced Pterideae. — 

 Sir Thos. Muir : Note on Pfaffians with polynomial 

 elements. 



Paris. 

 Academy of Sciences, March 22.— M. Henri Deslandres 

 in the chair. — A. Lacroix : The eruptive rocks of the 

 Pyrenees Cretaceous and the nomenclature of the 

 modified eruptive rocks.— G. Bij?ourdan : The pupils of 

 the Observatory of the College de France. The 

 observatories of the Military School.— F. E. Fournier : 

 General expressions for the resistance of water to the 

 passage of "ships floating in open air and for the wave- 

 length of their satellite surge.— A. Haller and R. 

 Cornubert : The constitution of the dimethylcvclo- 

 hexanone obtained by methylation of the sodium 

 derivative of a-methvlcvcJohexanone. From a studv of 

 the condensation products with benzaldehvde it is 

 concluded that the dimethylrycZohexanone is unsym- 



