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NA TURE 



[December 2. 1897 



" mineralisation " Mr. W. H. Merritt said that what he 

 thought of special interest was the mode of occurrence of the 

 gold in these conglomerates. He said that this showed that 

 auriferous solutions may occur in a very unexpected manner, 

 and in very unexpected places ; and in confirmation of this he 

 alluded to a locality in British Columbia where gold occurred, 

 and was worked in deposits of cupriferous pyrrhotite containing 

 virtually no free quartz and occurring chiefly in gabbro. The 

 Rev. J. F. Blake and Dr. J. W. Gregory also spoke. The 

 author, replying to the President, admitted that in describing the 

 ancient crystalline rocks he had used the term " Primary " indis- 

 criminately with " Archiiean." He agreed that it would perhaps 

 be better to discard the former, and to use the latter term in 

 preference. With regard to the age of the Cape formation, he 

 had pointed out in the paper that the Witwatersrand beds were 

 probably correctly correlated with the Table Mountain sand- 

 stone, and that the latter was underlain by the Bokkeveld shales, 

 in which characteristic Paljeozoic (Devonian) fossils had been 

 found. Replying to Prof Le Neve Foster, he instanced the 

 Nigel Mine as one that had been opened up in payable ore on 

 the south side of the synclinal. There was nothing to indicate 

 ■which of the conglomerate-beds might carry gold, short of taking 

 samples for panning or assay. He saw no objection to the use 

 of the word " mineralisation" to indicate a secondary impregna- 

 tion with mineral matter. He was glad to find that Dr. Gregory 

 confirmed him in the idea that the Dwyka conglomerate was a 

 volcanic breccia, and consequently indicative of volcanic activity. 

 — Observations on the genus Aclisina, de Koninck, with de- 

 scriptions of British species, and of some other carboniferous 

 gastropoda, by Miss J. Donald, of Carlisle. The author made 

 some preliminary observations on the genus Aclisina, and con- 

 sidered it advisable to regard A. puhhra as the type of the genus, 

 while the so-called A. striahila must be placed among the 

 Mtirchsoniic, and A. nana is placed in a new genus. 



Entomological Society, November 1 7. — Mr. R.McLachlan, 

 F.R.S., Vice-President and Treasurer, in the chair. — Mr. Selwyn 

 Image exhibited male examples of Pieris l/rassiciE, with a black 

 spot on the disc of the forewings. They were bred from larvae 

 found on Trof-irolum at Lee, N. Devon, and six out of ten males 

 showed this variation. He also showed a dark aberration of 

 Vanessa rtrlica, taken at Copthorne in Sussex, and two fine 

 specimens of Plusia moneta taken at Valerian, near Balcombe, 

 Sussex. — Mr. M. Burr exhibited three new species of Rumanian 

 Orthoptera in illustration of a later communication. — On behalf 

 of Mr. T. D. A. Cockerell, of Mesilla, New Mexico, two 

 specimens of Synchloe lacinia from that locality were exhibited 

 to show the remarkable forms of variation found in individuals 

 occurring at the same time and place and on the same flowers. — 

 Mrs. Nicholl communicated a paper on the butterflies of Aragon, 

 and Mr. Burr a list of Rumanian Orthoptera. — Mr. Tutt read a 

 paper entitled " Some results of recent experiments in hybridi- 

 sing Tephrosia bistortata and Tephjvsia crepuscularia.'" 



Royal Meteorological Society, November 17. — Mr. E. 

 Mawley, President, in the chair. — Mr. R. H. Curtis gave the 

 results of a comparison between the sunshine records obtained 

 simultaneously from a Campbell-Stokes burning recorder and 

 from a Jordan photographic recorder. The Campbell-Stokes 

 recorder consists of a sphere of glass, four inches in diameter, 

 supported in a metal zodiacal frame. A card being inserted in 

 one of the grooves according to the season of the year, the sun 

 when shining burns away or chars the surface at the points on 

 which its image successively falls, and so gives a record of the 

 duration of bright sunshine. The Jordan recorder consists of a 

 cylindrical box, on the inside of which is placed a sheet of 

 sensitive cyanotype paper. The sunlight, which is admitted into 

 the box by two small apertures, acts on the paper, and travelling 

 over it by reason of the earth's rotation, leaves a distinct trace 

 of chemical action. In an improved pattern two semi-cylindrical 

 boxes are used, one to contain the morning, and the other the 

 afternoon record. The Campbell-Stokes instrument gives a 

 record of sun heat and the Jordan instrument a record of sun 

 light ; and whilst it is probably true that, as a rule, the burning 

 and chemical eff"ects vary directly with the brightness of the 

 sun's rays, yet it by no means follows that the conditions which 

 will produce the most active chemical action must necessarily 

 and always be those most favourable for burning. It has been 

 the opinion of most observers that the photographic instruments 

 yield a larger record than those of the burning type. In order 

 to set the matter at rest the Council of the Royal Meteorological 



NO. 1466, VOL. 57] 



Society determined to institute a comparison between ihe 

 Campbell-Stokes and the Jordan recorders, which should 

 thoroughly test the capabilities of the two instruments, and at 

 the same time afford trustworthy data for determining how far 

 the records yielded by the one may be accepted for comparison 

 with those obtained from the other. These simultaneous ob- 

 servations were carried out by Mr. E. T. Dowson, at Geldeston, 

 near Beccles, and extended over a period of twelve months. 

 The records were sent to Mr. Curtis for tabulation, who gave 

 the results of his examination in this paper. After describing 

 the methods adopted for the measurement of the records, Mr. 

 Curtis drew the following conclusions from the figures: (i) In 

 the case of the Campbell-Stokes instrument the records are 

 capable of being measured with a very fair degree of accuracy. 

 (2) The records of the Jordan instrument afford room for much 

 greater difference of opinion as to what ought to be tabulated, 

 and consequently measurements of the Jordan curves are open 

 to considerably more doubt than are measurements of the 

 Campbell-Stokes curves. (3) When the whole of the photo- 

 graphic trace which can be distinctly seen, but including 

 portions of it which are decidedly faint, has been carefully 

 measured, the amount will approximate sufficiently to that of 

 the Campbell-Stokes instrument to allow of records obtained 

 from both forms of instrument being compared inter se. From 

 an examination of the records at other stations it appears that 

 on some occasions the instruments have begun to record within 

 thirteen minutes after sunrise, and has continued up to ten 

 minutes before sunset. Mr. Curtis concluded his paper by 

 calling attention to various defects in the adjustment and work- 

 ing of the instruments, and pointed out how these might be 

 overcome. After the paper had been read, an interesting 

 discussion ensued as to the merits of the respective sunshine 

 recorders. 



Linnean Society, November 18. — Dr. A. Giinther, F.R.S., 

 President, in the chair — The President announced that since the 

 close of last session they had been so fortunate as to receive from 

 Prof. G. J. Allman, a former President of the Society, a portrait of 

 himself painted by Miss Busk, whose portrait of her late father 

 was now hanging near it. It was an excellent likeness, and he 

 was sure it would be highly valued. He moved that a vote of 

 thanks be recorded for the presentation, and this was unanimously 

 agreed to. — Mr. Alan F. Grossman exhibited photographs of a 

 fasciated lily {Lilitini awatutn), on which some information 

 was given by Mr. A. D. Michael. — Mr. R. Morton Middleton 

 exhibited and made remarks on some ants received from 

 Ephesus. These had been referred to in a previous communica- 

 tion as being made use of in Asia Minor for the purpose of hold- 

 ing together the edges of incised wounds by means of their 

 strongly-hooked and sharp mandibles {Jotirn. Linn. Soc, ZooL 

 vol. XXV. p. 405). The species was now identified as Cataglyphus 

 viatica, Fabr. Mr. Thomas Christy gave some additional in- 

 formation resulting from inquiries he had made of foreign 

 correspondenfs. — Mr. J. E. Harting exhibited a specimen of the 

 great black woodpecker (Picus tnartitis), lately received from 

 Colonel W. C. Dawson, of Weston Hall, Otley, Yorkshire, where 

 it had been shot in his presence by a friend on September 8. 

 It was shown that this could not be the bird which had re- 

 cently been lost from the Zoological Gardens, since the latter 

 did not escape until October 9. Allusion was made to the 

 numerous records of the occurrence of this species in England, 

 some of which at least seemed worthy of credence, since the 

 recorded specimens had been obtained, and were preserved in 

 the possession of trustworthy persons. Mr. Howard Saunders 

 expressed the opinion that there was no sufficient ground for 

 including Picus martius in the list of British birds, as from its 

 partiality for pine forests and its stationary habits, it was not 

 likely to be a voluntary visitor to this country. The President 

 remarked that the perfect state of plumage of the specimen 

 exhibited was satisfactory evidence of its not having recently 

 escaped from captivity ; and that the late Lord Lilford, the year 

 before his death (which occurred on June 17, 1896), had two 

 black woodpeckers in his aviary in Northamptonshire, and in 

 consequence of their ailing in health, had given them their 

 liberty. It seemed possible that one of these might be the bird 

 lately shot in Yorkshire. — Mr. J. E. Harting also exhibited in 

 the flesh a hybrid pheasant and black grouse, which had been 

 received that day from Shropshire. In appearance it precisely 

 resembled a similar hybrid of which a coloured figure is given 

 in early editions of White's " Selborne." — On behalf of Mr. 

 Leonard Lush, of Stonehouse, Gloucestershire, three white 



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