May .27, 1920] 



NATURE 



401 



markings. When the recessive spotting allelomorph (S') 

 of self-colour (S) is present with the epistatic factor, a 

 hite animal with dark eyes known as " Daruma " 

 Miowman) is produced. Mice which are homozygous 

 for D fail to develop whether S or S' is present in 

 addition. D is, therefore, a lethal factor, and can 

 only appear in the heterozygous condition, as is well 

 known to be the case with yellow mice. By this 

 analysis it is shown that a varied and apparently 

 continuous series of stages from dark-eyed white 

 through spotting to self-colour depends upon two 

 pairs of factors. 



Mr. T. W. Vaughan furnishes a comprehensive 

 account of the American Tertiary, Pleistocene, and 

 Recent coral-reefs in Bulletin 103 of the U.S. National 

 Museum, pp. 189-524, 1919, as the fore-part of a 

 paper describing fossil corals from the zone of the 

 Panama Canal, No naturalist — and in this term we 

 of course include the geologist who strives to under- 

 stand the past — can afford to overlook this important 

 summarv of recent work. Some readers may be 

 • startled by the statement that " the theoretic possibility 

 of the progressive change of a fringing reef into a 

 barrier, and later into an atoll, according to the 

 Darwin-Dana hypothesis, may not be denied, but no 

 instance of such a transformation has as yet been 

 discovered." But the author again and again em- 

 phasises the upward grov^^th of coral-reefs in keeping 

 pace with the submergence of the platforms on which 

 thev first arose. The discussion of these platforms 

 and of their pre-Glacial age is full of interest ; but 

 Mr. Vaughan rightly points out that the question of 

 their modes of origin does not affect the question of 

 reef-growth. Murray's theory of solution to account 

 for lagoon depths is regarded as "entirely disproved," 

 and every credit is given to "Dr. Guppy and Admiral 

 Sir J. Wharton for their views on the relation of 

 reefs to submarine platforms. The corals that result 

 in barrier-reefs flourish, as Guppy urged, at some 

 distance from a shore, because they are there removed 

 from deleterious sediments; the reef thickens, as 

 Wharton jjerceived, by submergence of its base. In 

 the case of Australia, though not as a general pro- 

 position, Mr. Vaughan believes that this submergence 

 (an be accounted for by the rise of water during 

 • deglaciation." The effects of drift-currents in 

 developing and controlling the form of atolls on an 

 open platform may be regarded as well established. 



The Italian State Department has now resumed 

 publication of its Reports of the Aeronautics Experi- 

 mental Institution {Rendiconti dell' Istituto speri- 

 mentale acronautico). No. i of the new series just 

 to hand contains an exhaustive article on the treat- 

 ment and preservation of wood. The first part of 

 this important monograph deals with the botanical 

 aspect of the subject; the second part with the 

 theory of timber preservation, including drying and 

 seasoning; the third part with the practical side of 

 timber seasoning and irnpregnation with preserva- 

 tives ; while part iv. is devoted to methods of testing 

 (both physical and mechanical). 



Measures are being taken to reorganise and ex- 

 tend various scientific services in French Indo-China. 

 NO. 2639, VOL. 105] 



M. Aug. Che\-alier, writing in La Gdographie for 

 April (vol. xxxiii.. No. 4), gives some account of the 

 plans. The agricultural, forest, and sur\'ey depart- 

 ments had fallen into neglect when the present 

 governor-general in 1917 took steps to revive them. 

 Several experimental agricultural stations and agri- 

 cultural schools have been founded, and this year 

 work was begun on the building of a central scien- 

 tific institute at Saigon, to which the agricultural 

 service of Indo-China and the botanic gardens at 

 Saigon are to be attached. The institute will con- 

 duct experiments in the growth of rubber, coffee, 

 tea, and rice ; study the flora and products generally 

 of Indo-China ; and conduct researches on plant 

 diseases. It is also proposed to start a marine 

 station. The Government has provided funds for 

 a scientific library and the issue of a monthly agri- 

 cultural bulletin. 



No. 23 of the Proceedings of the Dutch Meteoro- 

 logical Institute is devoted to three papers by Miss 

 A. van Vleuten on the possibility of accounting for 

 the daily variations of the earth's magnetic field by a 

 system of electric currents external to the earth and 

 the currents within the earth's surface induced by them. 

 In 1889 Schuster concluded that such was the case. 

 Since that date both Fritsche and Steiner have 

 examined the data available, and concluded that it 

 did not support the hypothesis. In view of this 

 difference of opinion Miss van Vleuten has again 

 analysed the daily variation of the field, and re- 

 solved it into an external and an internal part. 

 The two show that the principal terms of the Gauss 

 expansion do not support the hypothesis, although the 

 higher and less important terms are in agreement with 

 it. In a further paper the author, by comparing the 

 terms of the potential calculated, first, from the north 

 component, and, secondly, from the east component 

 of the field, shows that the daily variation of the 

 field does not possess a potential, although it is, of 

 course, always possible to deduce part of it from a 

 potential. 



The physiological aspect of flying at high altitudes 

 engages the attention of Dr. Guglielminetti in Gdnie 

 Civil for March 20. The experiences of mountaineers, 

 balloonists, and airmen who have flown to great 

 heights are reviewed in turn. From tests carried out 

 in the laboratory, and from the experience of Mosso 

 and Agazotti (of Turin), Dr. Guglielminetti is in- 

 clined to the opinion that the physiological disturb- 

 ances caused at altitudes below 8000 metres are due 

 to ano.xyphemia, and above 8000 metres to acapnia. 

 While the use of respirators having suitable reducing- 

 valves controlled automatically by the varying pressure 

 at different altitudes would no doubt afford a fairly 

 satisfactory solution, the better way lies in the design 

 of suitable closed cabins in which the air-pressure is 

 maintained constant by compressing the air taken in 

 from outside. M. Louis Breguet has already sug- 

 gested a design of aeroplane in which the pilot and 

 passengers would be so enclosed. The excess of air 

 necessary for the engine at high altitudes would prob- 

 ably be supplied by a turbine driven by the exhaust 

 gases, such as has been suggested by Prof. Rateau. 



