246 



NATURE 



[December 22, 1910 



chloride of lime be added the water becomes unpalatable, 

 but the taste disappears on standing, particularly in bright 

 sunshine, or may be destroyed by the addition of a 

 dechlorinising agent such as bisulphite of soda. The 

 efficiency of chlorine and chloride of lime for sterilising 

 water has been amply demonstrated by many observers — 

 Nesfield, Rideal, Thresh, Woodhead, and others. 



In view of the recent scare of plague in the Eastern 

 Counties, considerable interest attaches to a paper by 

 Captain W. D. H. Stevenson (Scientific Memoirs by 

 Officers of the Medical and Sanitary Departments, India, 

 No. 38) giving a preliminary account of experiments on 

 the killing of rats and rat-fleas by means of hydrocyanic 

 acid, generated by the action of sulphuric acid on 

 potassium cyanide. Fleas were killed very rapidly by the 

 gas. In one experiment a mixture of i ounce of 

 potassium cyanide, 2 ounces of sulphuric acid, and 

 4 ounces of water was placed in a small room of the 

 capacity of about 346 cubic feet, and the door was then 

 closed. After forty minutes the door was opened, 

 and fifteen minutes later the room was entered ; all the 

 fleas left in different parts of the room were killed, even 

 those placed inside four bags, three of blanket and one of 

 cotton, but some of the fleas placed inside a box of clothes 

 survived. Rats were found to require more gas and a 

 longer exposure than fleas. On the other hand, plant-life 

 appears to be uninjured by the gas, and cultures of 

 bacteria were also unaffected by it. Dried grain is not 

 made poisonous for food by the gas, nor are its powers of 

 germination impaired in any way. Moist food-stuffs, how- 

 ever, such as water, milk, butter, and flesh, are said to 

 absorb the poison, and should therefore be removed from 

 a building during fumigation. The gas has no action on 

 metals or fabrics. 



That dorbeetles and their kindred are generally infested 

 with mites in this country is a well-known fact, but it 

 appears to be a comparatively new discovery that in 

 Cej'lon beetles of this group are likewise infested by minute 

 species of flies. In the December number of the 

 Entomologist's Monthly Magazine Mr. J. E. Collin 

 describes a new species of small hairy flies of the genus 

 Limosina taken from a coprophagous beetle in Ceylon. 

 The flies were found clinging to the under surface of the 

 beetle, and, instead of attempting to fly away, allowed 

 themselves to be dropped into a collecting tube without 

 change of position. 



In British Birds for December it is stated that about 

 7900 birds were ringed in this country during the year, 

 Messrs. Smalley and Robinson having marked no fewer 

 than 2313 out of this number. In the editor's opinion it 

 is at present too early to decide whether the results will 

 repay the trouble and expense involved in marking. Its 

 chief results will relate to the movements of individual 

 birds, and it is urged that special attention should be 

 paid to the recapture of the smaller marked birds by the 

 editor's corresjxvndents, most of those which have been 

 taken having fallen into the hands of persons unacquainted 

 with the scheme. The costs of the inquiry during last 

 year considerably exceeded the funds at the disposal of its 

 promoter, and if the scheme is to be continued next season 

 it can only be by the aid of special subscriptions. 



In the Proceedings of the United States National 

 Museum (vol. xxxix., 1910, pp. 37-91) Mr. R. E. Snod- 

 grass, whose treatise on the structure of the honey-bee 

 was noticed in Nature of December 8 (p. 169), publishes 

 an important memoir on the thorax of the Hymenoptera. 



NO. 2147, VOL. 85] 



In this paper the modification and elaboration of th 

 thoracic skeleton in the various families of the order ai 

 described in detail, and illustrated by nineteen text-figur<- 

 and fifteen plates. The author finds no support foi 

 Verhoeff's theory that each thoracic segment is a complex 

 of three primitive somites, but prefers to regard the 

 serially arranged sclerites of the mesonotum and meta- 

 notum — so fully shown by many Hymenoptera — as evidence 

 of specialisation. 



In vol. v.. No. 3, of the Philippine Journal of Science 

 Mr. L. E. Griffin publishes additional information with 

 regard to the pearl-fishery, dealing in this instance with 

 the products obtained off Bantayan, an island lying 

 between the northern ends of Negros and Cebu, at the 

 head of the Tanon channel. In May and June, and again 

 in November and December, the water is usually so still 

 and clear that the bottom can be seen to a depth of eight 

 fathoms, and it is at these seasons that the natives look 

 for oysters. In place of forming banks, these occur 

 sporadically, and were it not for the shortness of the season 

 there is little doubt they would long ago have been 

 exterminated. The shells, although of relatively small 

 size, are of excellent quality, but they are chiefly valuable 

 on account of the large percentage of pearls they yield 

 and their fine quality. During the present year one pearl 

 of the value of Sol. was collected, while others worth 

 from 20I. to 4oi. each were obtained. The total annual 

 value of the fishery is about 900Z. 



A SURVEY of the vegetation on the Kasatzkisch steppe, 

 near Kursk, is contributed by Mr. V. Alechin to the 

 botanical section (part ii.) of Travaux de la Societe des 

 Naturalistes de St. Petersbourg (vol. xli.). The main 

 feature is the great predominance of dicotyledons, although 

 Carex humilis takes an important part in the ground cover. 

 The author concludes that the steppes existed previousl 

 to the wooded areas, and that they have been but liti' 

 modified by human agency. 



The suitability of bamboos and lalang, or cogon grass, 

 for making pa{>er pulp is considered by Mr. G. F. Rich- 

 mond in an article on Philippine fibres published in the 

 Philippine Journal of Science (Section A, vol. v.. No. 4). 

 Proceeding upon evidence furnished by other investigators 

 and by laboratory experiments, the author takes a favour- 

 able view of the prospects of a local soda pulp mill for 

 treating bamboos, and supplies an estimate of the prob- 

 able cost. Also it is stated that a supply of raw material 

 and the necessary fresh water could be obtained in several 

 localities. 



Bud-rot disease of palms has been notified within recent 

 years from the West Indies, Ceylon,, India, and the 

 Philippine Islands, but in most cases the cause of the 

 disease has not been definitely established. Dr.. E. J. 

 Butler, who has conducted the investigations in India, 

 where palmyra palms are chiefly attacked, attributes the 

 disease there to a Pythium, deriving his conclusions from 

 the inoculation of healthy palms. The source of the 

 disease in the other countries, where cocoanut palms are 

 infested, is probably different. Dr. Butler has embodied 

 his latest researches, together with a general account of 

 the distribution and remedial measures adopted, in the 

 botanical series (vol. iii.. No. 5) of the Memoirs of the 

 Department of Agriculture in India. Two spore forms 

 are recognised ; in the ordinary case the contents of a 

 sporangium break up into zoospores, but in hot, dry 

 weather a resting variety of conidium is more commonly 

 found. 



