May 28, 1891] 



NATURE 



95 



sharp line of demarcation between the former and \^^ Avicula 

 (ontoria Shales. Most of the characteristic fossils of the British 

 Rhaetic are met with at Pylle Hill, together with a few forms 

 which are new to England, and some of these possibly to science. 

 A detailed section of the subdivisions of the Rhaetic and adjacent 

 beds, and a list of Rhsetic fossils found in the section are givei 

 by the author. After the reading of the paper some remarks 

 were made by Mr. Etheridge, Mr. H. B. Woodward, the Rev. 

 H. Winwood, and Prof. T. Rupert Jones. — A microscopic 

 study of the Inferior Oolite of the Cotteswold Hills, including 

 the residues insoluble in hydrochloric acid, by Edward Wethered. 

 The author gives the following main divisions of the Inferior 

 Oolite of the Cotteswold Hills in descending order : — 



Ragstones. 



Upper Freestones. 



Oolitic Marl. 



Lower Freestones. 



Pea Grit. 



Transition Beds resting on Upper Lias. 



The strata are described, and the results of microscopic examina- 

 tion of the different beds given. These latter confirm the author's 

 views as to the important part which Girvanella have taken 

 in the formation of oolitic granules ; whilst an examination of 

 the borings referred to by Prof. Judd in the discussion of Mr. 

 Strahan's paper " On a Phosphatic Chalk," convinces the author 

 that these have no connection with the genus Girvanella. In 

 the second part of the paper the insoluble residues left after 

 treating the various deposits with acid are considered. They 

 contain chiefly detrital quartz, felspars, zircons, tourmaline, 

 chips of garnet, and occasionally rutile. In the argillaceous 

 beds silicate of aluminia was found to occur plentifully. The 

 detrital material is considered to be due to denudation of crystal- 

 line felspathic rocks, and not of stratified ones. This view seems 

 to be supported by the quantity of felspar and its good state of 

 preservation. The paper concludes with a consideration of the 

 quantity of residue and the size of the quartz-grains in the 

 different deposits, which are summarized in the following 

 table :— 



Percentage Size of 



of quarti-grains, 



residue. in millim. 



Ragstones 2*8 ... •17 



Upper Freestones ... I'l ... 'iz 



Oolitic Marl 3*2 ... -09 



Lower Freestones ... i*8 ... '13 



Pea Grit Series 5-0 ... '14 



Transition Beds 38*3 ... '13 



This shows a great falling off in the percentage of residue above 

 the Transition Beds. That of the Freestones is remarkably low, 

 and it would appear that these rocks were formed under condi- 

 tions which allowed of very little sediment being deposited. The 

 paper gave rise to a discussion, in which Prof. Hull, Mr. 

 Etheridge, Mr. H. B. Woodward, the Rev. H. Winwood, and 

 the author took part. 



Royal Meteorological Society, May 20. — Mr. Baldwin 

 Latham, President, in the chair. — The following papers were 

 read : — On the vertical circulation of the atmosphere in relation 

 to the formation of storms, by Mr. W. H. Dines. After giving 

 an outline of the circulation of the atmosphere, the author refers 

 to the two theories which have been suggested to account for the 

 formation of storms, viz. (i) the convection theory, which is that 

 the central air rises in consequence of its greater relative warmth, 

 this warmth being produced by the latent heat set free by con- 

 densation ; and (2) the theory that the storms are circular eddies } 

 produced by the general motion of the atmosphere as a whole, , 

 just as small water eddies are formed in a flowing stream of 

 water. The author is of opinion that the convection theory is 

 the more probable of the two, but more information about the 

 temperature of the upper air is greatly needed. — On Brocken 

 spectres in a London fog, by Mr. A. W. Clayden. During the 

 dense fogs in February last, the author made a number of ex- 

 periments with the view of raising his own spectre. This he 

 ultimately succeeded in accomplishing by placing a steady lime- 

 light a few feet behind his head, when his shadow was projected 

 on the fog. He then made some careful measurements of the size 

 and distance of the spectre, and also succeeded in taking some 

 photographs of the phenomenon. — An account of the " Leste," 

 or hot wind of Madeira, by Dr. H. Coupland Taylor. The 

 "Leste" is a very dry and parching wind, sometimes very hot, 



NO. II 26, VOL. 44] 



blowing over the island from the E.N.E. or E.S.E., and corre- 

 sponds to the sirocco of Algeria, or the hot north winds from the 

 deserts of the interior experienced in Southern Australia. 

 During its prevalence a thin haze extends over the land, and 

 gradually thickens out at sea until the horizon is completely 

 hidden. It is most frequent during the months of July, August, 

 and September, and usually lasts for about three days. — Mr. 

 Shelford Bidwell, F.R.S., exhibited an experiment showing the 

 effect of an electrical discharge upon the condensation of steam. 

 The shadow of a small jet of steam cast upon a white wall is, 

 under ordinary conditions, of feeble intensity and of a neutral 

 tint. But if the steam is electrified, the density of the shadow 

 is at once greatly increased, and it assumes a peculiar orange- 

 brown hue. The electrical discharge appears to promote 

 coalescence of the exceedingly minute particles of water con- 

 tained in the jet, thus forming drops large enough to obstruct 

 the more refrangible rays of light. It is suggested that this 

 experiment may help to explain the intense darkness, often 

 tempered by a lurid yellow glow, which is characteristic of 

 thunderclouds 



Linnean Society, April 16. — Prof. Stewart, President, in 

 the chair. — A paper by the Rev. F. R. Wilson, was read, on 

 lichens from Victoria, in which several new species were described, 

 specimens of which were exhibited. — A paper by Surgeon-Major 

 A. Barclay followed, on the life-history of two species oi Piicciniay 

 viz. P. coroiiata, Corda, and a new species which the author 

 proposed to name P. Jasmini-chrysopogonis. A feature of 

 peculiar interest noted in the latter species was the extra- 

 ordinary abundance and wide distribution Qf the teleutosporic 

 stage as compared with the comparative scarcity of the ascidial 

 stage, and this disproportion in the distribution of the two 

 stages had been remarked by the author long before he had 

 ascertained that they were related. — A discussion followed, in 

 which several of the botanists present took part. 



May 7. — Prof. Stewart, President, in the chair. — Prof, R. J. 

 Anderson exhibited a panoramic arrangement for displaying 

 drawings at biological lectures. — Mr. John Young exhibited a 

 nest of the Bearded Titmouse (Calamophilus biarmicus), which 

 had been built in his aviary. Several eggs were laid, but none 

 of them were hatched. — The Rev. E. S. Marshall exhibited 

 several specimens of a Cochlearia from Ben More, believed to 

 be undescribed. — Mr. Robert Deane forwarded for exhibition a 

 plant of the Rayless Daisy, found growing abundantly in the 

 neighbourhood of Cardiff ; and an undetermined Sponge, dredged 

 in about 40 fathoms, off the coast of South Wales. — Mr. D. 

 Morris drew attention to a Jamaica drift fruit recently foiind on the 

 coast of Devonshire. Although figured so long ago as 1640 by 

 Clusius, and subsequently noticed by other observers, the plant 

 yielding it had only lately been identified by Mr. J. H. Hart, of 

 Trinidad, as Sacoglottis amazonica. Mr. Morris likewise ex- 

 hibited specimens of the fruit of Catostemma fragratts, received 

 for the first time, from St. Vincent, showing its true position to 

 be amongst the Malvacece, tribe Bombacecz. — Mr. Thomas 

 Christy exhibited some Kola nuts, and made remarks on the 

 properties attributed to their medicinal use. — A paper was then 

 read by Mr. Malcolm Lawrie, on the anatomy of the genera 

 Pterygotus and Slimonia, and their relationship to recent 

 Arachnida. An interesting discussion followed, in which the 

 President, Prof. Howes, Dr. H. Woodward, and others took 

 part. 



Entomological Society, May 6. — Mr. Frederick DuCane 

 Godman, F.R.S., President, in the chair.— Dr. D. Sharp 

 exhibited a number of eggs of Dyiiscus marginalis laid on the 

 sheath of a species of reed, and commented on the manner of 

 their oviposition, which he said had been fully described by Dr. 

 Regimbart. — The Rev. A. E. Eaton exhibited a collection of 

 PsychodidcE from Somersetshire, including six species of Psychoda, 

 eleven species of Periconia, and one species of Ulomyia. Mr. 

 McLachlan commented on the interesting nature of the exhi- 

 bition. — Mr. P. Crowley exhibited a specimen of Prothoe Cale- 

 donia, a very handsome butterfly from Perak ; and a specimen 

 of another equally handsome species of the same genus from 

 Tonghou, Burmah, which was said to be undescribed. — Mr. H. 

 Goss, the Secretary, read a letter from Mr. Merrifield, pointing 

 out that the statement made by Mr. Fenn, at the meeting of the 

 Society on April i last, of his views on the effects of tem- 

 perature in causing variation in Lepidoptera, was incorrect ; 

 he (Mr. Merrifield) had never suggested what might happen to 

 TcBuiocampa instabilis, and had expressly stated that he had 



