NATURE 



[March 20, 1913 



Edinburgh. 



Royal Society, February 17.— Dr. Home, F.R.S., 

 vice-president, in the chair.— Helen Pixell : Polychseta 

 of the families Serpulidae and Sabellidae, collected by 

 the Scottish National Antarctic Expedition. Eight 

 genera were represented in the collection, including 

 four new species, one in Apomatus, two in Spir- 

 orbis, and one in Potamus. — Dr. J. R. Milne and H. 

 Levy : The recording of fluctuating flow : its difficult 

 ties and errors. Owing to the inertia of its moving 

 parts, any instrument employed to record either "in- 

 stantaneous values " or the " time integral of a fluc- 

 tuating quantity " is liable to err. The extent of this 

 error is in many cases unknown, e.g. in the case of 

 a Robinson cup anemometer; and the present paper 

 describes some experiments made with an analogous 

 instrument to elucidate the matter. From the results 

 obtained it appears that fluctuation in the flow causes 

 the instrument to read too high. 



March 3.— Prof. Bower, F.R.S., vice-president, in 

 the chair. — Dr. R. A. Houstoun, A. H. tiray, and C. 

 Cochrane : The absorption of light by inorganic salts 

 (three concluding papers of a series). No. IX. dealt 

 with salts of copper, cobalt, and nickel dissolved on 

 alcohol and acetone, and described a successful attempt 

 to apply the mathematics of mass action to the change 

 of colour in an alcoholic solution of cobalt bromide 

 when water was added. No. X. was occupied more 

 particularly with the bearing of new methods on the old 

 controversy of the colour of the ions, and it 

 was shown conclusively that the colour changes 

 of the cobalt, nickel, and copper salts have 

 nothing whatever to do with ionisation. In 

 No. XI. Dr. Houstoun discussed the theoretical 

 aspect of the results gained and the present state of 

 research in the field. — Dr. G. A. Carse, G. Shearer, 

 and H. Jameson : Note on a comparison of records of 

 atmospheric potential at two stations in Edinburgh. 

 The two stations were the Physical Laboratorv of the 

 University and the Royal Observatory, Blackford 

 Hill. A large number of records were compared, and 

 the curves for the two stations showed in general 

 good agreement, the agreement being best in those 

 which_ indicated a disturbed state of the atmosphere. 

 This is interesting when it is considered that the 

 University is in the centre of the town and the ob- 

 servatory in the clearer air of the outskirts, nearlv 

 two miles distant. 



DUBLIN'. 



Royal Dublin Society, February 25.— Prof. J- Wilson 

 in the chair. — Dr. G. H. Pethybridge : The rottin<* of 

 potato tubers by a new species of Phytophthora having 

 a method of sexual reproduction hitherto undescribed. 

 A new form of rot in potato tubers is described, in 

 which the cut surface of affected tubers when exposed 

 to air turn at first pink and afterwards nearly black. 

 The causative organism is a new species of Phytoph- 

 thora, to which the name P. erythroseptica is "given. 

 Sexual organs are produced when the fungus is 

 grown artificially as a saprophyte, and probablv also 

 in nature. At an early stage in its development the 

 young oogonium penetrates the antheridium at or near 

 the base of the latter, grows up through it, bursts out 

 at the summit, where it swells to form the oogonium 

 proper, in which the oosphere and oospore develop. 

 Fertilisation, if it takes place at all. probably occurs 

 while the oogonial incept is within the antheridium, 

 and hence before the formation of the oosphere. The 

 sexual organs of P. Phaseoli, P. infestans, and prob- 

 ably P. omnivora, var. Arecae, are developed in a 

 similar manner, but those of P. cactorum, P. fagi, 

 P. Syringae, and probablv others, follow the usual 

 course, where the antheridium penetrates the 

 oogonium laterally. Species which follow this latter 

 NO. 2264, VOL. 91] 



method are removed from the genus Phytophthora, 

 and are placed in a new one, to which the name 

 Nozemia is given. — Dr. G. H. Pethybridge and P. A. 

 Murphy : Pure cultures of P. infestans, de Bary, and 

 the development of oospores. An account is given of 

 the cultivation of P. infestans as a saprophyte on 

 various media, on some of which (Oat-Agar and 

 Quaker Oat-Agar) sexual organs are developed. 

 Clinton's discovery of undoubted oospores is con- 

 firmed, and the mode of their formation is explained 

 by the process occurring in P. erythroseptica. — Prof. 

 J. Wilson; Inter-alternative as opposed to coupled 

 Mendelian factors : a solution of the agouti-black 

 colour in rabbits. This is an alternative solution to 

 that t'iven by Prof. Punnett in the November (1912) 

 number of The Journal of Genetics as to the agouti- 

 black colour in rabbits. Prof. Punnett found three 

 factors acting conspicuously. On the "presence and 

 absence" theory each of these must have its 

 "absence." Thus there were six in all, and to meet 

 the case two of the three prominent factors had to be 

 coupled. The author finds that there are five factors 

 operating in the case, viz. three dominants and two 

 recessives, but that two of the dominants, and one of 

 the recessives are inter-alternatives — that is, any one 

 of the three can alternate with either of the other 

 two, just as happens with the black, white, and red 

 colours of cattle, or with the colours of horses. — E. G. 

 Fenton : Notes on recent pampa and other formations 

 in Patagonia. The author, from his traverses of 

 southern Patagonia, brings forward evidence of wide- 

 spread glacial and ice-sheet conditions at the close of 

 Pliocene times, followed by a long inter-glacial in- 

 terval, during which extensive outpourings of lava 

 and emission of exploded materials occurred. This 

 interval, which may have lasted for some thousands 

 of years, was followed by a more local glaciation, 

 when the Andes sent glaciers into the lowlands. The 

 author believes that elevation of the area is now in 

 progress. 



Paris. 

 Academy of Sciences, March 3. — M. F. Guyon in the 

 chair. — B. Baillaud ; The publication of certain works 

 of the Paris Observatory. — A. Lacroix : The minera- 

 logical constitution of the Los Archipelago (Guinea). 

 —Paul Sabatier and A. Mailhe : A catalytic method of 

 isomerising the alkyl chlorides and bromides. 

 Chloride of barium or chloride of thorium at 250 C. 

 decompose the alkyl chlorides and bromides into acid 

 and ethylenic hydrocarbon. If this mixture is passed 

 over pumice in the same tube heated to 200 C. these 

 gases re-combine, giving secondary and tertiary alkyl 

 halides. Examples of the application of the method 

 are given. — Charles Deperet : Observations on the 

 Pliocene and Quaternary geological history of the 

 Gulf and Isthmus of Corinth. — M. Barbier was elected 

 a correspondant for the section of chemistry in the 

 place of the late M. Ladenburg. — Charles Nordmann : 

 The light yield of a black body at high temperatures 

 and on that of the stars. First application to Arcturus 

 and Vega. By the application of Planck's and 

 Stefan's laws it is shown that the light yield of a 

 radiating body increases with the temperature to a 

 maximum and then decreases. As a first approxima- 

 tion this temperature is found to be 6430 C, very 

 nearly that found by various methods for the sun. 

 The effective temperature of Arcturus is deduced as 

 -,400° C, and Vega is 2-2 times as great.— M. 

 Tzitzeica : Derived reciprocal networks. — J. Le 

 Roux : The determination of the harmonic functions. 

 Application to the square. — Mile. Th. Tarnarider : The 

 best approximation of |.r| 2 »+ 1 by polynomials of in- 

 definitely increasing degrees. — Jacques Chapelon ; The 

 numbers of classes of positive binary quadratic forms. 



