January 7, 191 5] 



NATURE 



525 



specialisation carried so far as to preclude a thorough 

 training in all the fundamental branches of the sub- 

 ject. The courses in applied chemistr}-, metallurgy, 

 electro-chemistry, and sanitary and industrial biology- 

 serve to prepare students as scientific experts and for 

 professional positions in manufacturing establishments 

 and Government laboratories. Thorough courses in 

 pure science, namely, in chemistry, physics, biology, 

 geology, and general science, are also arranged. 



SOCIETIES AND ACADEMIES. 

 London. 

 Linnean Society, December 17, 19 14. — Prof. E. B. 

 Poulton, president, in the chair. — M. Christy ^ A remark- 

 able gall believed to be new in this country. The gall is 

 in the nature of a " witches'-broom," but appears on 

 Salix fragilis ; whereas no "broom" of the kind has 

 hitherto been recorded on any species of willow in this 

 country. It appears in great abundance on all trees 

 of the species named growing in proximity. Accord- 

 ing to Prof. Xalepa, it is due to a gall-mite Eriophyes 

 triradiatiis, but not improbably a parasitic fungus may 

 assist. So far, the gall is confined, apparently, to a 

 limited area within a radius of, say, twelve or fifteen 

 miles around London. The gall is remarkable in that 

 it appears on the female flower, which develops during 

 summer, until it resembles a bunch of moss, of an 

 olivaceous green colour, from 2 to 8 in. in length, 

 hanging from a small twig. The bunch consists of 

 hundreds, perhaps thousands, of abnormal flowerets. 

 — W. M. Webb: The Brent Valley Bird Sanctuarv'. 

 Twelve years ago the Brent Valley Branch of the Sel- 

 borne Society took steps to protect a wnod of nineteen 

 acres in its district, not far from Ealing, which had 

 long been known as an abiding place for birds. The 

 immediate object was to preserve the nightingales ; 

 and a small committee was formed to approach the 

 tenant of the farm on which the wood was situated 

 with a view to the appointment of a watcher. Ulti- 

 mately, the committee appointed its own keeper, took 

 over the wood from the farmer, and now rents it 

 direct from the owners. No very rare birds occur in 

 the wood, but it is important in the neighbourhood of 

 large towns to give an opportunity to the commoner 

 kinds of nesting undisturbed. Forty-one species have 

 been recorded as breeding in the wood, thirt}--nine of 

 them during recent years. Among these may be 

 mentioned the nightingale, lesser whitethroat, the 

 blackcap, garden-warbler, chiffchaff, willow-warbler, 

 long-tailed tit, marsh-tit, tree-creeper, hawfinch, gold- 

 finch, redpoll, nuthatch, wryneck, cuckoo, red-backed 

 shrike, turtle-dove, and wild duck. Including the 

 winter migrants and occasional visitors, eighty-eight 

 species have been obser\'ed in or close to the wood. 

 Of these, the golden-crested wren, all the three British 

 woodpeckers, the nightjar, the brown owl, the barn 

 owl, the snipe, and the kingfisher are seen commonly 

 or from time to time. Owing to the introduction of 

 nesting-boxes, several species have increased in num- 

 bers or have been induced to nest. 



Dublin. 

 Royal Dublin Society, December 15, 19 14. — Prof. W. 

 Brown in the chair.T-J. Doyle : The change of the petiole 

 into a stem by means of grafting. A sprout was grafted 

 on a petiole of Pelargonium zonule, v. meteor, all 

 the other buds and leaves being removed. After a 

 short time the petioles carried large plants, completely 

 functioning as stems, while the qualities of a stem, 

 viz., indefinitely active cambium, the appearance of 

 interfascicular cambium, considerable secondary 

 thickening, periderm formation, were all taken on by 

 the petiole. The possible causes of this secondan.' 

 thickening are to be sought (i) in the removal of 



NO. 2358, VOL. 94] 



correlational influences; (2) in increased mechanical 

 strain ; (3) in some influence exerted as a result of 

 foliar development. This influence is probably bound 

 up with the water economy of the plant — particularly 

 transpiration — but its precise nature has still to be 

 determined. — Prof. J. B. Butler and J. M. Sheridan : 

 A preliminary' account of a new oedanometer for 

 I measuring the expansive force of single seeds or 

 j similar bodies when wetted. The apparatus described 

 1 consists of two strong iron castings bolted together, 

 I and holding between them a diaphragm of sheet 

 I rubber. The seed to be tested is dropped through a 

 cylindrical passage in the lower casting on to the 

 rubber diaphragm. It is then packed round with fine 

 sand, and covered by a disc of wire gauze. A strong 

 plunger is screwed firmly home on the seed and sand, 

 packing it tightly. Water can be admitted through 

 holes drilled in the plunger. A hemispherical space 

 directly over the rubber diaphragm in the upper cast- 

 ing contains mercury, which is in communication with 

 a fine bore thermometer tube containing air. The 

 upper end of this tube is closed. When water is 

 admitted to the seed it swells ; the swelling force is 

 transmitted through the rubber diaphragm to the 

 mercurv, and thence to the air in the thermometer 

 tube, compressing it. In this way the pressure, 

 developed by one or more large seeds, can be 

 measured. From single broad-bean seeds pressures 

 of from 28 to 30 atmospheres were obtained. Six 

 peas placed in the apparatus registered from 45 to 50 

 atmospheres. — Prof. J. Wilson : An example of the 

 multiple coupling of Mendelian factors. The English 

 varieties of the campine breed of fowl are described 

 from the Belgian varieties, but are now slightly 

 different in type as regards plumage. The matings 

 by which the Rev. E. Lewis Jones and others pro- 

 duced the English type show that four factors are 

 coupled. If M = the male factor, F = female; E = Eng- 

 lish t>pe, b = Belgian; Bl.=: black colour, g = gold; and 

 Bd. =barred plumage, and = plain, the factorial re- 

 presentation of a BelgiaM ivpe "silver" campine hen 

 is 



The four factors placed in the closed bracket are 

 coupled.— Prof. H. H. Dixon and Miss E. S. Marshall : 

 A quantitative examination of the elements of the 

 wood of trees in relation to the supposed function of 

 the cells in the ascent of sap. Measurements of the 

 cross-sections of the various, elements of the wood of 

 various trees were made by weighing the parts of 

 cut-out photomicrographs of the wood. In this way 

 the percentage of the total cross-section occupied by 

 vessels, tracheids, cells, and walls was determined. 

 The assumption that the transpiration current is 

 raised by the protoplasmic streaming in the cells is 

 shown to be untenable owing to the velocity of 

 streaming it would require. — Prof, H. H. Dixon and 

 W. R. G. Atkins : Osmotic pressures in plants. 

 Part iv. — The constituents and concentration of sap 

 in the conducting tracts, and on the circulation of 

 carbohydrates in plants. Throughout the year appre- 

 ciable quantities of carbohydrates are present in the 

 transpiration stream of trees. Their concentration is 

 always greater than that of the electrolytes. In 

 deciduous trees the concentration of the carbohydrates 

 attains a maximum in spring, and is at its minimum 

 in summer. In evergreens there are two cusps in the 

 concentration curve. The distribution of carbohydrates 

 '<; a function of transpiration no less important than 

 the conveyance of nutritive salts. The coating of 



