December 26, 1907] 



NA TURE 



then, the ideal cone as a skeleton, and clothing it with 

 matter within and without, a material double hollow cone 

 may be made of the form of a diabolo spool, but with the 

 dynamical properties of a sphere. It is preferable, how- 

 ever, to make the spool with an axial hole and with a 

 slight preponderance of moment of inertia about its rota- 

 tional axis. It will then spin perfectly. It may, however, 

 be easily adjusted by the insertion of a stick, which is cut 

 off of such a length as to make the moments of inertia 

 equal, as tested by suspension from a torsion wire. — .\ 

 gyroscope illustrating Brennan's mono-railway : Prof. H. A. 

 Wilson, A gyroscope is mounted in bearings so that it 

 can spin about a horizontal axis and precess freely. The 

 gyroscope is further mounted at the top of a rectangular 

 framework. The axis of spin of the wheel is first placed 

 at right angles to the plane of the framework. Attached 

 to the vertical axis about which the precessional motion 

 occurs is a short crank with a spiral spring attached, so 

 that when precession occurs in any direction the pre- 

 cessional couple is increased and the top returns towards 

 its initial position. The oscillations of the gyroscope about 

 its mean position become continually larger until the 

 stability of the arrangement disappears. 



Zoological Society, November 26 — Mr. G. A. Boulenger, 



F.R.S., vice-president, in the chair.— Some new and little- 

 known Araneidea : Rev. O. Pickard-Cambridge. Eleven 

 species were noted or described and figured : — one from 

 Lagos, Portugal ; three from Cape Colony, South Africa ; 

 one from Mashonaland ; five from the Canaries ; and one 

 from Old Calabar. Seven species were described as new to 

 science. Five of the spiders had been accidentally imported 

 to England in packages of bananas. — New species of beetles 

 of the cryptocephaline division of the family Chrysomelid^ 

 from tropical South America : M. Jacoby. — The correla- 

 tion of certain modifications of the limpet-shell {Patella 

 vulgata) with definite environmental conditions : E. S. 

 Russell. The method adopted by the author had been to 

 measure the dimensions of a large number of shells from 

 one environment and to compare them with similar 

 measurements of shells from a second environment. The 

 author had found the limpet a suitable animal for such 

 investigations, as all limpets above 15 mm. " home " 

 accurately. Limpets from high-water localities were found 

 to be larger, broader, and higher, but narrower in propor- 

 tion than those from low-water localities. Limpets from 

 exposed localities were lower, narrower, thicker, and more 

 irregular in outline than those from sheltered spots. On 

 the area from which the shells were collected two types 

 occurred, a " rough " type with strong coarse ribs and 

 irregular margin, associated with rough stones, and a 

 " smooth " type on polished stones. — .Anatomy of the 

 batrachian family Pelobatidae : F. E. Beddard. — The 

 Microlepidoptera of Tenerife : Lord Walsing^ham. — Dates 

 of publication of the separate parts of Gmelin's edition 

 (thirteenth) of the " Systema Naturaa " of Linnaeus : J. 

 Hopkinson. The paper stated that the first volume of this 

 edition, containing the animal kingdom, was in seven parts, 

 with a date, 1788, in the first part only, but that there 

 was internal evidence of a later date of issue of subsequent 

 parts. Investigations in the library of the British Museum 

 had revealed the years of publication with some indication 

 also of the period of the year in which each part appeared. 

 The dates were: — part i., 1788; parts ii. and iii., 1780; 

 parts iv. and v., 1790: part vi., 1791 ; part vii., 1792. The 

 second volume, containing the vegetable kingdom, was in 

 two parts, and the date of issue of part ii. had been found 

 to be 1792. Contemporary authorities were given for the 

 dates. — A small collection of Mammalia brought from 

 Liberia by Mr. Leonard Leighton : R. 1. Pocock. The 

 paper recorded the presence in Liberia of two mammals 

 hitherto unknown from that locality, and contained de- 

 srriptions of one species of Genet and one Linsang new to 

 ii i.nce. 



Dirember 10. — Sir Edmund G. Loder, Bt., vice- 

 |)vi-.ident, in the chair. — The origin of the mammal- 

 like reptiles : Dr. R. Broom. — A revision of the 

 .\frican silurid fishes of the subfamily Clariinae : G. A. 

 Boulenger. — A new species of haemogregarine from the 

 blood of a Himalayan lizard, Agama tuberciilata, from 

 Kasauli, India : Prof. E. A. Minchin. 



Society of Chemical Industry, December 2.^Mr. R. J. 

 Friswell in the chair. — The estimation of naphthalene in 

 coal gas and spent oxide of iron : C. J. Dickenson-Gair. 

 The methods of estimation described are (i) the acetic 

 acid method ; (2) the re-precipitation method. — Note on the 

 influence of formal on the properties of Ftintuiiiia clasiica : 

 Dr. P. Schidrowitz and F. Kaye. The authors find that 

 the rubber obtained from tlie latex, treated by formal, 

 although less elastic and resilient than that obtained by 

 other means, was extraordinarily tough. They suggest 

 that a rubber of this character might be particularly suit- 

 able for some purposes — e.g. for the covers of motor tyres — 

 where toughness is of relatively greater importance than 

 resiliency, and that it may in the future be found desirable 

 to use different methods of coagulation for the same latex 

 according to the purpose for which the rubber is intended. 

 — Polarimetric determination of sucrose : F. Watts and 

 H. A. Tempany. The authors have investigated (i) the 

 effect of basic lead acetate on the optical activity of sugar 

 solutions ; (2) the effect of clarification with basic lead 

 acetate on cane juice. — Niam fat : Dr. J. Lewkowitsch. 

 Niam fat was obtained from the seeds of Lophira alula. 

 Banks, a tree indigenous to Senegambia, Sierra Leone, 

 and the Egyptian Soudan. The fat, freed from extraneous 

 matter, forms 41 per cent, of the kernels. It is a soft, 

 buttery mass melting at 24° C, and is used by the natives 

 for culinarv purposes and as a hair oil. 



Entomological Society, December 4. — Mr. C. O. 

 Waterhouse, president, in the chair. — Exhibits. — Dr. G. C. 

 Hodgson: .\ number of examples of .-liithroccra trifoUi. 

 collected on the same ground in Sussex, and showing a 

 wide range of variation, including three fine melanic 

 forms, and several showing six spots on the upper-wings. 

 — W. J. Kaye : .\ specimen of Papilio thoas thoas, with 

 the central portions of both tails removed, apparently by 

 a narrow-billed bird. The injury appeared so symmetrical 

 that it was thought likely that the specimen was an 

 abnormality, but microscopical examination showed that 

 this was not so.— The President : Two photographs of 

 an African locust, which had apparently caught a mouse 

 and was preying upon it. The specimen was found in the 

 Congo State'. — R. S. Bagnall : Notes on many species of 

 Coleoptera, Thysanoptera, and Aptera from Northumber- 

 land, Durham, and Scotland, of which ten were new to 

 Britain.— L. W. Newman : A long and varied series of 

 Ennoinos autumnaria (alniaria) ; a series of Folia xantho- 

 mista {nigrocincta), bred from ova and fed on carrot, the 

 specimens unusually large (N. Cornwall) ; three pairs of 

 hybrid Xotodonta ziczac c? X N. dromcdnrius C , = iV. 

 newmani. Tult : three very fine Xylina contoniiis bred by 

 Evan John, S. Wales ; three cocoons {in situ) of Dicramira 

 bicuspis, collected wild in Tilgate Forest ; and a^ fine 

 melanic' c? Oporabia dilutata, taken wild in Bexley Woods, 

 1907, this being the first melanic specimen of the species 

 reported from Kent.— Dr. F. A. Dixey : Male and female 

 specimens of a new Belenois allied to B. zochalia, Boisd., 

 but quite distinct from the zochalia group. These were 

 captured by Mr. Wiggins in the Tiriki Hills, north-east of 

 the Victoria Nvanza. — Papers. — (i) The natural enemies of 

 Bombyx riibi fn Scotland; (2) note in further illustration 

 of the convergence of Limenitis (Basilarchia) in America : 

 Prof. E. B. Poulton. — The rest attitude of Hyria 

 auroraria: J. C. Moulton. — The family tree of moths and 

 butterflies, traced in their organs of sense : .\. H. 

 Swinton. — Notes and descriptions of Pterophoridse and 

 Orneodida; : E. Meyrick. — Studies on the Blattid.-e : R. 

 Shelford. — Notes on the bionomics of British East .African 

 butterflies : Rev. K. Si. A. Rogers. 



Ge-)logical Society, Decemb r 4. — Sir Archibald Geil;ie. 

 K.C.B., Sec.R.S., president, in the chair.— The faunal 

 succession in the Carboniferous Limestone (Upper 

 Avonian) of the Midland area (north Derbyshire and north 

 Staffordshire) : T. F. Sibly. The area is the periclinal 

 mass at the south end of the Pennine anticline. The 

 series exposed constitutes an expanded development of the 

 Dibunophyllum zone. The most extensive section shows^ a 

 thickness of 1500 feet. Three subzonal divisions are dis- 

 tinguished : — bj, subzone of Cyathaxonia nishiana ; D,, 



NO. 1 99 1, VOL. 77] 



