June i6, 1904] 



NA TURE 



159 



vertical circulation of the atmosphere between the tropics 

 and the poles, and he expresses the hope that the terms 

 " polar " and " equatorial " currents, which have hitherto 

 caused so much confusion in dynamical meteorology, will 

 disappear completely from meteorological science. In his 

 important paper he shows, for instance, that in all parts 

 of the temperate zone of the northern hemisphere an 

 upper current from west to east prevails in all months of 

 the year, while in the tropical zone the currents at all 

 heights are almost without exception from east to west. 

 Apother important contribution, by M. L. Teisserenc 

 de Bort, on barometric depressions at various altitudes, is 

 contained in the excerpt above referred to, which corro- 

 borates the conclusions arrived at by Dr. Hildebrandsson. 



Three papers on terrestrial magnetism from the reports 

 of the U.S. Coast and Geodetic Survey for 1902 and 1903 

 have just been received. In a paper on " Magnetic Observ- 

 atories of the United States Coast and Geodetic Survey," 

 Dr. L. A. Bauer and Mr. J. A. Fleming describe very 

 fully the various points which have to be considered in 

 determining suitable sites for magnetic observatories, and 

 the question whether the elimination of magnetic material 

 in the construction of observatories is essential when used 

 only for observations of variations and not absolute values 

 is discussed. A description of three observatories is given, 

 and the paper is illustrated with maps of the selected sites 

 and with views of the observatories and of the instruments 

 used. A paper on " Magnetic Dip and Intensity Observ- 

 ations (January, 1897, to June 30, 1902)," by Mr. D. L. 

 Hazard, gives full details of the magnetic elements deter- 

 mined at 800 stations — about one-fifth of the total number 

 proposed for the general magnetic survey. In addition to 

 the field observations, the variations of declination and of 

 the horizontal intensity are recorded photographically at 

 four observatories, at each of which the absolute values of 

 the elements are determined at least once a week. Much 

 difficulty was found in obtaining concordant results with 

 different dip circles ; subsequently an earth-inductor was 

 selected as a standard dip instrument. In the third paper 

 — " Results of Magnetic Observations made by the Coast 

 and Geodetic Survey between July, 1902, and June, 1903 " 

 — Dr. L. A. Bauer describes the method of taking field 

 observations, and gives tables of the results and a full de- 

 scription of each station used for the observations. It is 

 evident that every precaution is taken that each station 

 may be accurately located at any future date. 



Among our weekly budget of pamphlets, we may refer 

 to a copy of the Proceedings of the South London Entom- 

 ological and Natural History Society for 1903, and also to 

 one of the Proceedings of the Philadelphia Academy for 

 April. The latter contains an important paper, by Dr. D. B. 

 Castell, on the cell-lineage and larval development of the 

 nudibranch mollusc Fiona marina. 



Mr. W. E. Clarke has favoured us with a copy of a 

 paper from the Proceedings of the Royal Physical Society 

 of Edinburgh (vol. xv., part ii.) in which he describes, 

 under the name of Mus miisculus faeroensis, a new form of 

 house-mouse from the Faeroes. Large size and certain 

 peculiarities in colour are the distinctive features of this 

 race. 



The medusas of the Bahamas form the subject of the first 

 issue of a new serial (vol. i., \o. i) — the Memoirs of Natural 

 Sciences — published by the Brooklyn Institute. Compared 

 ■with that of the Tortuga Islands, off Florida, the medusa- 

 fauna of the Bahamas has been found by the author — Mr. 

 A. G. Mayer — to be comparatively poor. This is accounted 

 NO. 1807, VOL. 70] 



for by the circumstance that the Tortugas stand in " blue 

 water," whereas the Bahamas are surrounded with shallow 

 flats of coral-mud, very sterile in animal life generally. 



A.v important discovery with regard to the breeding of 

 the cod is recorded by Mr. T. W. Fulton in the Publications 

 (No. 8) of the International Council for the Exploration of 

 the Sea. .As a rule, cod spawn from January to June — 

 chiefly in March — but some of these fish recently taken on 

 a patch of rocky ground in the North Sea lying to the 

 north-east of Aberdeen, off the coast of Norway, were found 

 to be spawning in September and October. It was already 

 known that the herring has a spring and an autumn spawn- 

 ing season, and now we have proof that, in one area at any 

 rate, the same holds good for the cod. An interesting point 

 for determination is whether there is any difference between 

 the spring and the autumn fry. 



Dr. C. W. Andrews, of the British Museum, has recently 

 returned from Cairo, where he had been studying the fine 

 series of vertebrate remains from the Fayum district. A 

 number of specimens have, we understand, been acquired 

 by exchange for the British Museum, while the series in 

 the museum of the Egyptian Geological Survey at Cairo 

 has been arranged and developed by Mr. Barlow, jun., of 

 the formatori's staff at the Natural History Museum, who 

 went out some months ago for that purpose. Among the 

 more important specimens at Cairo is a young skull of 

 Arsinoitherium zitteli, exhibiting the cranial sutures, and 

 thus permitting the identification of the bones from which 

 the huge front horns arise. 



For nearly twenty years Mr. F. M. Webster, of the 

 Illinois Natural History Laboratory, has been endeavouring 

 to find a means of mitigating the plague of " buffalo-gnats " 

 (Simulium invenustum), which of late years have proved so 

 disastrous to cattle-owners in the districts bordering the 

 lower course of the Mississippi. The remedy is a simple, 

 although somewhat expensive one, namely, to prevent the 

 great river from overflowing its banks, for it is in such 

 overflows that these noxious little flies breed, and thus over- 

 run the country. That their ravages are no trifling matter 

 may be gathered from the statement that in 1882 a farmer 

 in Louisiana lost 3200 head of stock from their attacks. 

 Wild animals are terribly tormented by these pests, and 

 a white-tailed deer has actually been known to rush into 

 a blacksmith's forge to obtain relief in the smoke from their 

 bites. 



A PAPER on " Fertility in Sheep," by Mr. F. H. A. 

 Marshall (Trans. Highland and Agric. Soc, Scotland), 

 directs the attention of stock breeders to certain points of 

 practical interest which are discussed in a recent memoir 

 by the author on the cestrous cycle in the sheep, published 

 in the Philosophical Transactions, and noticed in Nature of 

 September 3, 1903 (yol. Ixviii. p. 429). The paper concludes 

 with suggestions for future investigations on fertility in 

 the ewe. 



Mr. Thomas Burleigh has published a second edition of 

 Mr. E. F. Chidell's " Africa and National Regeneration " 

 (pp. 78). The preface to the new issue occupies more than 

 half the pages of the book. 



The list of spectroscopes and spectroscopic accessories 

 just issued by Messrs. Adam Hilger, Ltd., is conveniently 

 arranged, and supplies useful information concerning a great 

 variety of instruments for general work and for special 

 purposes. Among other mleresting apparatus described we 

 notice film replicas of Rowland's diffraction gratings with 

 14,438 lines per inch, and the Michelson echelon diffraction 

 gratings with the number of plates ranging from ten to 

 forty. 



