98 



NA TURE 



[November 22, 1900 



between the species named, and considered such hybrids of rare 

 occurrence, while examples of a cross between blackcock and 

 pheasant were not nearly so uncommon. Mr. Howard Saunders 

 regarded the little owl (Carine noctua) as having little if any 

 claim to be considered a British bird ; its occasional appearance 

 in England being due to the fact that a good many had been 

 turned out from time to time in different counties. — Mr. George 

 Massee exhibited a series of coloured drawings and an extensive 

 collection of fungi. — Dr. Charles Chilton, M.A., F.L.S., read a 

 paper on the terrestrial isopods of New Zealand. — M. J. E S. 

 Moore read a paper on the character and origin of the " park- 

 lands " in Central Africa. These park-lands in the Tanganyika 

 district have quite the appearance of having been formed by the 

 hand of man, but are really natural growths, due to the fact that 

 light surface-soil has been laid down over what appear to have 

 been lake-deposits. Any given line of country will show large 

 plantations, with quite a home-like look, separated by grass- 

 lands ; and, as Tanganyika is approached, they dwindle in size 

 till they consist of a few shrubs, overshadowed by giant euphor- 

 bias, cactus-like in appearance. Then come stretches of grass, 

 dotted with euphorbias, and, last of all, the salt steppes by the 

 lake, which is now held to have had at one time an outlet to the 

 sea. Mr. Moore's explanation is that at first only the euphorbias 

 would grow on the salt steppes ; but as these sprang up they 

 afforded a shade and shelter to self-sown shrubs, each of which, 

 as it established a footing, contributed to the natural planting of 

 the area by the distribution of its seeds, till this process reached 

 its highest development in the large plantations where the shrubs 

 overtopped the euphorbias to which they owed their growth. 



Geological Society, November 7.— J. J. H. Teall, F.R.S., 

 President, in the chair. — Additional notes on the drifts of the 

 Baltic coast of Germany, by Prof T. G. Bonney, F.R.S., and 

 the Rev. E. Hill. The authors, prior to revisiting Riigen, 

 examined sections of the drift to the west of Warnemiinde, with 

 a view of comparing it with that of the Cromer coast. The 

 authors give reasons to show that neither solution of the chalk, 

 nor ice-thrust, nor folding, nor even faulting, can satisfactorily 

 explain the peculiar relations of the drift and chalk in Riigen ; 

 and they can find no better explanation than that offered in 

 their previous paper. — On certain altered rocks from near 

 Bastogne and their relations to others in the district, by Dr. 

 Catherine A. Raisin. Prof. Renard, from the petrographical 

 study of specimens, and Prof. Gosselet, after description of the 

 district and its stratigraphy, have attributed the changes in these 

 rocks to mechanical disturbances. Dumont had previously 

 described many examples, and inclined to the view of contact- 

 alteration, which was favoured by Von Lasaulx's discovery of a 

 granite in the Hohe Venn, and M. Dupont's identification of 

 chiastolite from Libramont. The present paper treats especially 

 of the garnetiferous and hornblendic rocks, giving the full petro- 

 graphical and field-details of a few examples. It points out 

 that the effects of pressure are evident over the whole district, 

 while mineral modifications resembling the results of slight 

 contact-action are found in certain areas. In a few cases these 

 modifications are more marked, and sometimes increase as we 

 approach veins composed of quartz, felspar and mica, such as 

 might be connected with a concealed granite. The peculiar 

 garnetiferous and hornblendic rocks, although occurring within 

 the zone of alteration, are extremely limited, often forming 

 patches or bands a few feet across. They differ, as described in 

 the paper, from ordinary contact-altered rocks. The evidence, 

 in the authoress's opinion, is in favour of Prof. Bonney's sug- 

 gestion that they are due to some form of hot-spring action. 



Entomological Society, November 7. — Mr. G. H. Verrall, 

 President, in the chair. — Mr. G. S. Saunders exhibited speci- 

 mens, from Devonshire, of Pieris rapae and Plusia gamma, 

 caught by the proboscis in flowers of Ararijia albens, Don. , a 

 climbling plant of the natural order Asclepiadaceae ; and ex- 

 plained the nature of the mechanism by which the insects were 

 entrapped by the flowers. lie also showed specimens of the 

 "bedeguar" gall formed apparently on the " hips," or fruit, of 

 Rosa canina. Mr. Gahan remarked that the capture of insects 

 by the plant named had recently been investigated in France by 

 MM. Marchand and Bonjour, whose account appeared in the 

 Bulletin de la Soc. des Sciences Nat. de I'Ouest de la France, 

 for 1899. These authors concluded that insects were captured 

 only by immature flowers, the anther-wings, in the cleft between 

 which the proboscis of the insect is caught, being at that time 

 stiff and resistant ; but when the flowers are ripe the anther- 



NO. 162 1, VOL. 63] 



wings become less rigid and do not offer sufficient resistance to 

 the withdrawal of the proboscis, which carries with it the pollinia 

 ready to be transferred to the stigma of the next flower visited 

 by the insect. — Mr. W. J. Kaye exhibited Zi^^/rocaw/a j/a^«a/zV, 

 var., with examples of the typical form for comparison; the 

 variety differed in having the basal line nearly obsolete, the sub- 

 median double line much strengthened internally and reduced 

 externally, and the cross band connecting the sub-median and 

 post-median bands almost entirely obliterated. — Mr. F. Merri- 

 field exhibited a variety of Argynnis dia taken- with a few 

 examples of the ordinary form at llanz in the Vorder Rhein 

 valley early in September last, when what was, he believed, a 

 third brood of this species, was abundant ; the variety was much 

 blackened on the basal half of all the wings. — Canon Fowler 

 exhibited a specimen of Orochares angustatus, Erichs. , a 

 Staphylinid beetle new to the British list, taken at Leverstock 

 Green, Herts, by Mr. Albert Piffard.— The Rev. F. D. Morice 

 mentioned, as a fact of some interest, that in a nest of Formica 

 sanguinea at Weybridge, in which he found males and workers 

 of that species, he found also males and females as well as 

 workers of the slave-ant Formica fusca, an experience somewhat 

 different to that of Huber and Darwin, who stated that workers 

 only of the slave species were found in the nests of sanguinea. — 

 The Secretary read " Some notes on variations of Zeritis thy she, 

 Linn.," communicated by Mr. H. L. L. Feltham, and exhibited 

 one female and two male specimens of one of the rare forms 

 referred to in the paper. 



Mathematical Society, Nov. 8.— Lord Kelvin, G.C.V.O., 

 President, in the chair. — Reports from the Treasurer and 

 Secretaries were read and received. The ballot was taken and 

 the gentlemen whose names appeared in Nature for October 

 18 were declared to have been duly elected to serve on the 

 Council for the session 1900-1901. Lord Kelvin, on leaving 

 the chair, thanked the Society for having elected him to the 

 office, and regretted that the distance (400 miles) of his home 

 from town had caused him to be so rarely able to take the chair. 

 He then cordially welcomed his successor, Dr. Hobson, and 

 expressed his pleasure in having him for his successor. The 

 new President thanked the members for electing him, and then 

 called upon Lord Kelvin to deliver his address '* On the trans- 

 mission of force through a solid." The address was a very 

 interesting one, and on the motion of Dr. Glaisher, seconded by 

 Dr. Larmor and backed by the acclamation of the members 

 present, Lord Kelvin consented to put his remarks into a shape 

 fitted for publication in the Society's Proceedings. — Dr. Glaisher 

 then communicated two papers : (i) A general congruence 

 theorem relating to the BernouUian function ; (ii) On the 

 residues of BernouUian functions for a prime modulus, including 

 as special cases the residues of the Eulerian numbers and the 

 I-numbers. — Mr. Tucker next communicated some notes on 

 Isoscelians, and gave a few properties of two in -triangles similar 

 to the pedal triangle. These triangles have their sides perpen- 

 dicular to the antiparallels of the primitive triangle. — The 

 President communicated the remaining papers by simply reading 

 their titles. In a simple group of an odd composite order every 

 system of conjugate operators or subgroups includes more than 

 fifty, Dr. G. A Miller. — Prime functions on a Riemann surface. 

 Prof. A. C. Dixon. — On Green's function for a circular disc, 

 H. S. Carslaw. — On the real points of inflection of a curve, 

 A. B. Basset. — On quantitative substitutional analysis, A. 

 Young. — On a class of plane curves, J. H. Grace. — (i) On 

 group characteristics, and (ii) On some properties of groups of 

 odd order. Prof. W. Burnside. — (i) Conformal space transforma- 

 tions, and (ii) Dynamical and other applications of algebra of 

 bilinear forms, T. J. Bromwich. 



Mineralogical Society, November 13. — Prof. A. H. 

 Church, F.R.S., President, in the chair.— Mr. G. F.Herbert 

 Smith described an improved form of his three-circle goniometer, 

 in which the use of an autocollimating telescope obviates the 

 disadvantage of the original instrument that measurements could 

 only be made through 93°. — Mr. Harold Hilton gave a simple 

 proof of the rationality of the anharmonic ratio of four faces of 

 a zone. — Mr. R. H. Solly, in continuation of the investigation 

 of sulpharsenites of lead from the Binnenthal, described the 

 crystallographic characters of rathite. 



Manchester. 

 Literary and Philosophical Society, October 30. — Prof. 

 Horace Lamb, F.R.S., President, in the chair. — A paper on the 

 solubility of certain lead glasses or fritts used in the preparation 



