July 23, 1908] 



NATURE 



279 



undertaken at the Carnegie Institution of Washington are 

 recorded by Mr. C. B. Davenport in publication No. 95 

 of that body, the report being illustrated with three 

 coloured plates. After referring in some detail to the in- 

 troduction and cult of the canary as a cage-bird, the 

 author observes that in some respects this species, owing 

 to the comparatively short time it has been under the 

 influence of domestication, is better adapted for investiga- 

 tions of this nature than animals which have been longer 

 subject to human influence. As regards colour, it appears 

 that the domesticated yellow breeds are derived from the 

 original " green " breed by the loss of the black, and 

 that it consequently carries a mottling factor which leads 

 to the production of mottled hybrids when crossing takes 

 place with a pigmented canary or a finch. .Although such 

 hybrids do not display a fixed pattern, the degree of 

 their mottling is heritable. Further, the principle of 

 localisation of the unit of complex plumage-colour must 

 be recognised, as is exemplified by the restriction of a 

 red patch to the sides of the face in hybrid canary- 

 goldfinches. 



On the occasion of succeeding to the presidency of the 

 Royal Microscopical Society for the second time, Lord 

 .Avebury delivered an address on seeds, with special refer- 

 ence to British plants. The president confined himself to 

 a synopsis of the forms occurring in the British dicotyledon- 

 ous orders and indicated the biological significance of the 

 various devices met with. The paper is printed in the 

 June number of the society's journal. 



From Messrs. Gallenkamp and Co., London, n new 

 catalogue of museum jars and window aquarium apparatus 

 has been received. It also contains an illustrated list 

 of Smedley's models. The models of Palreozoic seeds and 

 cones, which are on view in the Hall of Science at the 

 Franco-British Exhibition, have met with the universal 

 approbation of botanists ; the models of cryptogamic 

 plants, flowers and seeds, and of invertebrates, are less 

 generally known. They are all modelled in hard wax on 

 a rigid foundation. 



The editorial article in the June number of Tropical Life 

 deals with the arrangements made for insurance against 

 gales, hurricanes, and earthquakes as applicable to Jamaica 

 and other West Indian islands. These permit of the 

 insurance of such crops as limes, cocoa, and cocoanut-trees. 

 Cotton can be specially insured against damage during 

 the hurricane months July to October. In the same journal 

 Mr. F. T. Crawley discusses the value of manures for 

 lands planted with sugar-canes. With reference to the 

 experience of planters in the Hawaiian islands, it is stated 

 that fertilisers containing ammonia, phosphoric acid and 

 potash are found to lead to an increased proportion of 

 sucrose. 



Having for twenty years pursued the study of the resin- 

 ous substances found in plants, Dr. A. Tschirch laid before 

 the Chemical Society of Switzerland, in response to its 

 invitation, a paper treating of the chemistry and biology 

 of plant secretions, with special reference to the resins. 

 The author classifies the resinous substances according 

 to the various products that are associated with the pure 

 resin, and distinguishes taimol resine, rcsinol resine, and 

 harzsaiirc, also such extraneous substances as ethereal 

 oils, gums, &c. With reference to their systematic value, it 

 is observed that while the orders Dipterocarpacese, 

 Burseraceae and others are characterised by definite groups 

 of resins, other resins occur in plants quite unrelated. But 

 it is suggested that for distinguishing between certain 



NO. 2021, VOL. 78] 



resin-producing species, chemical tests based on the secre- 

 tions might be devised. The lecture has been published 

 in pamphlet form. 



The results of an expedition in the Atlas Mountains of 

 Morocco, made by M. Louis Gentil in 1906-7, are given 

 in La Geographic for March. From the data obtained, a 

 valuable map has been drawn up, indicating the main 

 geological features of the High Atlas Mountains from the 

 west coast to the region of Demnat. In an article accom- 

 panying the map, M. Gentil discusses the various difficul- 

 ties encountered in obtaining accurate observations, and 

 emphasises the utility of geological methods in mountain 

 exploration. Information has been obtained of the hitherto 

 little-known regions of Ounila, Anr'mer, Sous, and Siroua, 

 the characteristic geological structure of the last being 

 especially noticed. In an orographical sketch of Morocco,, 

 the regions of the High Atlas, Middle Atlas, and .'\nti- 

 .\tlas are distinguished, and the main features shown ore 

 a map. 



Mr. W. H. Wheeler has prepared a paper on the 

 physical characteristics, tides, currents, and fisheries of the 

 North Sea (J. D. Potter, 145 Minories). In the first 

 section an account is given of the pre-Glacial condition 

 of the North Sea, the main features being a deep fiord 

 in the north branching out of the Atlantic, a large 

 estuary south of the Wash, and an isthmus joining England 

 to the Continent. In the post-Glacial period the mouth of 

 the fiord between Durham and Yorkshire became blocked 

 up, sandbanks were formed, and the channel which now 

 forms the Strait of Dover was scooped out. This section, 

 of the paper includes also a description of the Dogger 

 Bank, and illustrations of the depression of the land on 

 the east coast of England and in the Low Countries. The 

 making of new land by the deposit of glacial drift covered 

 by alluvium is discussed, e.xamples being drawn from the 

 coasts of Belgium and Holland. The opposite effect of 

 erosion is observed along the English coasts. An account 

 is given of the Orkney and Shetland Islands, and the east 

 coasts of Scotland and England are described in detail. 

 The progress of the tidal wave in the North Sea is traced, 

 velocities and range of the tides being given, with a table 

 showing the effect of winds on the tides. As the result 

 of experiments made by the Fishery Board of Scotland, 

 the general drift of the surface currents in the North Sea 

 was shown to be southerly down the coasts of England' 

 and Scotland, then south-east round the Dogger Bank, 

 and, finally, east-north-east to the Skager-rack. Statistics 

 of the fishing industry are given in the section dealing with 

 this subject. 



The first application of the Kimberley method of diamond 

 washing to the concentration of alluvial tin is described' 

 by Mr.. H. D. Griffiths in the Mining Journal of July 11. 

 The new method has been adopted at Kuils River tin 

 mines, Cape Colony, and has given such exceptional 

 results as regards efficiency and economy that the sluicing 

 methods formerly in use on the property have now been 

 discarded. 



The British Fire Prevention Committee has issued a 

 red book (No. 127) on fire tests with fire extinguishers. 

 The series of tests with the " Diamond " dry powder 

 extinguisher showed that hand powder fire e.xtinguishers, 

 as a class, if applied with skill, can often be usefully 

 employed in the incipient stages of small fires. The 

 various tests undertaken with petrol point to the con- 

 clusion that, with a volatile liquid of this nature giving 

 off a highly inflammable vapour, the powder extinguisher 

 is only efficient when the area of the fire is small 'or 



