August 1 6, 1888] 



NATURE 



383 



is President of Section C (Geology). Among other points which 

 he is likely to discuss will be the following : — That .n the history 

 of life on the earth the more complex forms have changed more 

 swiftly than the simpler, because they are more susceptible to 

 changes in their environment. That in the Tertiary age the 

 highest of all, or the placental mammals, are the only forms 

 which have changed with sufficient swiftness to mark the sub- 

 divisions of the Tertiary period. They alone are en pleine 

 evolution. The borderland between geology and history will 

 be discussed, and the present series of events shown to belong 

 to the Tertiary period. The place of man in the geological 

 record will be considered (pre-glacial). The impossibility of 

 fixing historic dates for geological events will also be discussed. 

 Outside the written record a sequence of events can alone be made 

 out, in which we are ignorant of the length of the intervals. 

 In Section D (Biology), of which Mr. Thiselton Dyer, 

 Director of Kew Gardens, is President, no doubt we may 

 expect some of those discussions on subjects of general biological 

 interest which have been so marked a feature of the Section since 

 Prof. Ray Lankester was its President at Southport. Colonel 

 Sir Charles Wilson presides over Section E (Geography), and 

 his address will deal largely with the commercial aspects of geo- 

 graphy. In Section F (Economics), of which Lord Bramwell is 

 President, the Presidential address is likely to be biief, and will 

 deal with the general principles of political economy, and with 

 socialism in particular. Mr. W. H. Preece, of the Telegraph 

 Department, will preside over Section G (Mechanical Science). 

 In his address he will pass under review the various practical 

 applications of electricity, with the introduction of nearly all of 

 which Mr. Preece has been more or less associated. He will 

 also probably say something about the present views of the 

 theory of electricity, about which practical electricians and pure 

 physicists are at entire variance. Finally, in Section H (Anthro- 

 pology), the address of the President, General Pitt-Rivers, is, 

 like Lord Bramwell's, likely to be short. 



Discourses will be delivered in the Drill Hall — on Friday 

 evening, September 7, by Prof. W. E. Ayrton, F.R. S., on " The 

 Electrical Transmission of Power"; on Saturday Evening, 

 September 8 (to " the operative classes "), by Sir John Lubbock, 

 M.P., F.R.S., on "The Customs and -Ideas of Savage Races " ; 

 on Monday evening, September 10, by Prof. T. G. Bonney, 

 F.R.S., on "The Foundation Stones of the Earth's Crust." 



The Mayor of Bath invites the members and associates to a 

 conversazione in the Assembly Rooms on Thursday, September 

 6, at 8.30 p.m. The Chairman and members of the Local 

 Executive Committee invite the members and associates to a 

 conversazione at the Assembly Rooms, on Tuesday, September 

 11, at 8.30 p.m. On this occasion the Bath Microscopical 

 Society, assisted by the Bristol Microscopical Society, have 

 arranged for a display of objects in the various departments of 

 natural history, &c. No special cards of invitation will be 

 issued to these conversaziones, but all members and associates 

 will be admitted on presentation of their tickets. 



The concluding general meeting will be held on Wednesday, 

 the 12th of September, at 2.30 p.m. 



On Wednesday and Thursday, the 5th and 6th of September, 

 there will be an exhibition of fruits, flowers, &c, in the Sydney 

 Gardens ; to this exhibition all members and associates will be 

 admitted on presentation of their tickets. On the 12th and 13th 

 of September there will be a horse show in Bath ; but on this 

 occasion the members and associates will have no special 

 advantages. 



The following are the proposed excursions, arrangements for 

 which are in active progress : — 



Saturday, September 8.— Stanton Bury, Stanton Drew, Maes 

 Knoll : Bannerdown, Sodbury Camp, Dyrham, Lansdown : Box 

 Ouarries, Corsham, Lacock Abbey : Bradford, Farleigh Castle, 

 WraxaH : Cirencester, Museum and College : Tytherington and 

 Thornbury : Swindon, G. W. Works : Berkeley Castle : Wells, via 

 Maesbury and Shepton Mallet, Ebbor, Wookey Hole : Barry 

 Docks and Cardiff. 



Thursday, September 13. — Stonehenge, Salisbury, Wilton: 

 Silbury, Avebury, Bowood, Wansdyke, Beckhampton : Stourton, 

 Pen Pits, White Sheet, Longleat : Frome Valley, Nunney 

 Whateley : Maesbury, Wells, Glastonbury, Street : Sandford 

 and Banwell, Churchill, Dolbury, Rowberrow, Burrington, the 

 two Charterhouses, Mendip Gorge, Cheddar Cliffs : Severn 

 Tunnel, Chepstow, Tintern, Wyndcliffe : Radstock, Wellow, 

 Littleton. 



SOCIETIES AND ACADEMIES. 



London. 



Entomological Society, August 1. — Dr. D. Sharp, Presi- 

 dent, in the chair. — Mr. F. D. Godman, F.R.S., exhibited 

 a large number of species of Lepidoptera and Diptera 

 recently collected for him in Mexico by Mr. Herbert Smith. 

 — Mr. White exhibited parasites bred from Bombyx neustria, 

 and a living example of Heterodes guyoni, found at Dart- 

 ford, and believed to have been introduced with Esparto 

 grass from Tunis. — Mr. Enock exhibited a stem of barley, 

 showing the appearance of the plant under an attack of 

 Hessian fly. — Mr. Stevens exhibited a number of galls collected 

 at Byfleet in July last ; also a specimen of Coleophora solitariella, 

 with ichneumons bred from it. — Mr. E. Saunders exhibited a 

 specimen of Catephia alchymisla, captured at St. Leonards, in 

 June last. He also exhibited specimens of a rare ant {Anochetus 

 ghiliani), taken at Tangier by Mr. G. Lewis. One of these he 

 had submitted to Dr. Emery, of Bologna, who thought that, 

 although ocelli were present, the specimen was probably inter- 

 mediate between a worker and a female, and that possibly the true 

 female did not exist. — Mr. Pascoe exhibited a number of species 

 of Coleoptera recently collected in Germany and the Jura Moun- 

 tains, and read a note correcting the synonymy of certain species 

 of Brachycerns recently described by him in the Transactions 

 of the Society. He stated that the corrections had been sug- 

 gested by MM. Peringuey and Aurivillius. — Prof. Westwood 

 communicated a paper entitled "A List of the Diurnal Lepido- 

 ptera collected in Northern Celebes by Dr. Sydney Hickson, 

 with descriptions of new species." 



Edinburgh. 



Royal Society, July 16. — Rev. Prof. Flint, Vice-President, 

 in the chair. — Dr. Traquair read an obituary notice of Mr. 

 Robert Gray, Vice-President. — A paper by Prof. C. G. Knott, 

 Tokio University, on some relations between magnetism and 

 twist in iron and nickel, was submitted. — Mr. R. Kidston com- 

 municated a paper on the fossil plants in the Ravenhead col- 

 lection in the Liverpool Museum. — Prof. Crr.m Brown submitted 

 an investigation by Mr. Alex. Johnstone on the action of car- 

 bonic acid water on olivine. — In a paper discussing the question, 

 Is Talbot's law true for very short stimuli? Dr. G. N. Stewart, 

 Owen's College, describes experiments designed to test whether 

 it is possible to make the luminous stimuli so short that the 

 separate effects cannot be summed. He was able, by means of 

 a rotating mirror, to reduce the length of each stimulus to some- 

 thing like 1/8,000,000 sec. Up to this limit he could detect no 

 variation from the law. — Another paper by Dr. Stewart, on 

 some colour phenomena observed with intermittent stimulation 

 with white light, was communicated. When light of moderate 

 intensity is used, and the rate of stimulation gradually increased, 

 the colour is seen to change regularly in a manner which can 

 be explained on the assumption that the curves representing the 

 course of the excitation in the three hypothetical fibre-groups 

 run in such a way that with a certain length of stimulation time 

 the violet fibres are proportionally more stimulated than the 

 others ; with a shorter time of stimulation the green fibres are 

 more stimulated ; with a still shorter time, the red. — Dr. H. R. 

 Mill, Scottish Marine Station, discussed the specific gravity 

 of the water in the Firth of Forth and the Clyde sea-area. 

 — Dr. J. Macdonakl Brown read a paper on arrested twin 

 development. — The Chairman made some remarks in closing the 

 session. 



Paris. 



Academy of Sciences, July 30. — M. Janssen, President, in 

 the chair.— On the relations of atmospheric nitrogen to vege- 

 table soil, by M. Th. Schlcesing. The conclusion already 

 arrived at from previous researches (see Comptes rendus for 

 March 19 and 26, 1888) is fully confirmed by the results of the 

 subsequent series of experiments here described. Whether ex- 

 posed to renewed contact with the air, or kept in closed vessels 

 with a confined but oxygenated atmosphere, the soil with which 

 the experiments have been made has in no case fixed any ap- 

 preciable quantity of gaseous nitrogen. The author supplements 

 this communication with some remarks on the quantitative 

 analysis of the carbon and nitrogen in vegetable earths. The 



