October 17, 1907] 



NA TURE 



623 



variation in the adults, and consequently some periodic 

 selection. The records of Prof. Weldon for inheritance in 

 mice are reduced and discussed, so far as regards sex- 

 ratio and size of litter ; there is little, if any, inheritance 

 in cither case, but the figures exhibit some peculiarities. 

 The remaining articles include investigations by Prof. 

 F. Y. Edgcworth on the average time of absence of wasps 

 and bees from the nest, by Miss Wright, Miss Lee, and 

 Prof. Karl Pearson on the wing dimensions of wasps 

 (Ves^a vulgaris), and by Dr. J. Brownlee on means of 

 estim.ating the severity of attack in cases of acute disease. 

 There arc a few miscellanea, and a bibliography of litera- 

 ture on biometry and Mendelism relating chiefly to issues 

 of 1906. 



On the subject of apogamy in the fern genus Nephro- 

 dium, Mr. S. Yamanouchi communicates a preliminary 

 notice of his cytological investigations to the Botanical 

 Gazette (August). In the normal gametophyte of Nephro- 

 dium molle sixty-four or sixty-six chromosomes were 

 counted, and the double number in the sporophyte. In 

 the apogamous developments, the sporophyte was followed 

 from an initial cell, the nucleus of which contained the 

 smaller number of chromosomes, and the same number 

 was found throughout all the stages of the sporophyte. 



The first two numbers for the current year of the 

 Journal Botaniquc of the Imperial Society of Naturalists 

 in St. Petersburg contain two papers by Mr. A. Elenkin 

 on lichens. In the earlier he describes three new lichens 

 for the genera Eveinia, Aspicilia, and Lecania, all collected 

 in Russia ; in the later he discusses the comparative 

 amount of growth in erect and horizontally growing species 

 of close affinity. The description of a new species of 

 Eremurus from China derives its chief interest from the 

 fact that, as the author, Mr. O. A. Fedtschenko states, 

 this is the first record of that genus from China, and a 

 considerable extension of its distribution south-eastwards 

 beyond the previous limit in or near Nepal. 



Mr. C. E. C. Fischer contributes to the Indian Forester 

 (August) a list of host plants of various species of 

 Loranthus and Viscum observed in the North Coimbatore 

 Division of Madras. It is stated that these parasites are 

 most frequent in dry, deciduous forests at elevations 

 between 3500 feet and 4500 feet, where practically every 

 tree is attacked. The occurrence of one parasite grow- 

 ing on another parasite is recorded. The method of ex- 

 ploiting the trees of Terminalia Chebula for their fruits, 

 the myrobalams of commerce, is described by Mr. J. E. C. 

 Turner. The sound fruits become ridged when they are 

 dried in the sun, and the pericarp becomes exceedingly 

 hard ; others do not wrinkle, owing to the decomposition 

 attributed to a fungus of part of the mesocarp into 

 a black powder that has a small value for making ink. 

 For sowing, the damaged fruits are preferable, since 

 germination is not hindered by a hard pericarp. 



Within recent years an algal disease, known as the 

 " red rust " of tea, caused by Cepbaleuros viresccns, one 

 of the Chroolepida;, has become a serious pest in the tea 

 districts in India. Dr. H. H. Mann and Mr. C. M. 

 Hutchinson, scientific officers to the Indian Tea Associ- 

 ation, after following the course of the disease for some 

 years, have published an account of their observations in 

 the botanical series of the Memoirs of the Department of 

 Agriculture in India (vol. i., No. 6). The growth on the 

 leaf, being usually confined to the surface, would be un- 

 important, except for the fact that the sporangia there 

 formed provide the means for the spread of the disease. 

 NO. I 98 I, VOL. 76] 



This is effected either by transference of the sporangia as 

 a whole or of the zoospores. The real danger is due to 

 the penetration of the young stems of the tea plant by 

 the alga, when, if the alga prevails, the leaves turn white 

 and the stems are killed. 



It is well known that tide curves show that, in 

 addition to waves of very short duration due to wind, 

 and those caused by the regular flow and ebb of the tide, 

 pulsations sometimes called *' marine seiches '* or *' vibra- 

 tions of the sea " occur, with periods of fifteen to twenty 

 minutes, but differing considerably in various localities 

 (see Nature, January 12 and April 20, 1899). In the 

 Anniiario of the R. Nautical Institute of Catania, Sicily 

 (vol. i., 1907), Prof. Giovanni Platania contributes an 

 interesting paper on the subject, with the results of 

 some fresh researches made by himself in the Gulf of 

 Catania. Opinions differ as to the origin of these 

 vibrations, which are observed under different meteor- 

 ological conditions ; the author thinks that the principal 

 cause is variations of atmospheric pressure. The micro- 

 barograph recently devised by Dr. Shaw and Mr. Dines 

 for recording the minor and sudden fluctuations of the 

 atmosphere will probably help further to elucidate the 

 phenomenon. 



The current issue of the Central (vol. iv.. No. 12) con- 

 tains an interesting account of research work carried out 

 recently in the electrical department of the Central 

 Technical College. There is also a well-illustrated descrip- 

 tion of the cyanide process for the extraction of gold and 

 silver from their ores, written by Mr. Reginald Krall. 



The British South Africa Company has issued a 

 copiously illustrated monograph on Rhodesia, covering 120 

 pages. It contains much information for travellers 

 generally, and for sportsmen in particular. The illustra- 

 tions have been admirably reproduced, and the five coloured 

 maps are excellent. The volume should prove of special 

 use to teachers as a class-book. 



The mode of formation of many placer deposits is not 

 clearly understood, and the source of the gold has not been 

 definitely determined. In view of this uncertainty, a recent 

 paper by Mr. J. B. Tyrrell in Economic Geology (vol. ii.. 

 No. 4) is of special interest. He describes the conditions 

 that prevail in the Klondike district of Canada, a country 

 of exceedingly rich gold-bearing placers, where the origin 

 and processes of deposition and concentration of the gold' 

 into its present position are easily recognised. His in- 

 vestigations show that the district owes its phenomenally 

 rich placers, not to the wearing down of highly mineralised 

 gold-bearing veins, but rather to the favourable conditions 

 of long-continued and uninterrupted concentration from a 

 great mass of rock that contained only very minute quanti- 

 ties of gold. 



Three valuable monographs have been issued by the 

 Corps of Mining Engineers of Peru. In Boletin No. 51 

 Mr. F. M. Santolalla describes the mineral resources of 

 the province of Huamachuco. The mineral deposits may 

 be divided into three groups, the veins in eruptive rocks, 

 such as the gold veins of the Toro, the lead-antimony-silver 

 ores of Cerro Negro, and the magnetic iron ores of San 

 Pascual and Potosi de Serpaquino. The coal deposits of 

 the province have been known from time immemorial. In 

 short, the mineral resources might be worked with great 

 advantage if better means of communication were avail- 

 able. In Boletin No. 52 Mr. H. C. Hurd investigates 

 two schemes for diverting the waters of the Rio de- 



