December 22, 1898] 



NA TURE 



parasite — namely, Anopheles ciaviger. In this second successful 

 experiment the mosquitoes were brought from a distance from a 

 notoriously malarial spot, and liberated on the subject of the 



\, experiment in Rome. The investigators referred to have not yet 

 discovered Ross's " germinal rods ' in mosquitoes purposely fed 

 on crescent-containing blood. We hear, however, that they 

 have found these rods in mosquitoes brought from, a distance 

 from houses in which there had been malarial fever cases. 



! 



Mr. W. Garstang's paper on the variation, races, and 



} migrations of the mackerel [Scomber scomber), published in the 



} latest number of the Journal of the Marine Biological Associa- 



I tion, is a valuable contribution to a subject of economic as well 

 as of scientific importance. The investigation was undertaken 

 at the invitation of H.M. Trea.sury, and its chief object was to 

 ■discover the relation to one another of the spring and autumn 

 schools of mackerel which regularly visit the Irish coasts. In 



' the spring a multitude of large fish approach the south and west 

 coasts of Ireland to breed. In the autumn, schools of immature, 



1 but usually well-grown, mackerel come around the island. 



• These differences are explained by the facts collected by Mr. 



'' Garstang ; for it appears that the Irish race of mackerel may be 



■ subdivided into two distinct stocks. 



, The paramount conclusion of the inquiry of Mr. Garstang 



, into the life-history of the mackerel is thus expressed : " The 



, mackerel which frequent British waters are not exactly alike in 



J all localities, but possess certain average peculiarities which dis- 



,' tinguish one local race from another. These peculiarities are 



' -greatest between the races of localities which are geographically 



. remote, and least between those which occupy areas that are 



' geographically contiguous. Between the mackerel of the North 



Sea and English Channel there are no differences at all ; but the 



' Irish race is distinctly divisible into two stocks, one of which is re- 



I stricted to the west coast, the other to the south. A considerable 



I amount of mixture takes place between the southern Irish stock 



, and the fish which frequent the mouth of the English Channel. 



I The western Irish stock represents more closely than any other 



I race the primitive type of mackerel, from which all, whether 



I British or American, have been derived." It is pointed out that 



j the establishment of geographical or local races of the mackerel 



involves the rejection of the theory of long migrations. 



An abstract of a study of the more stable differences of a 

 physical nature which exist between white and negro children of 

 the same sexes and the same ages, is given by Dr. A. Hrdlicka in 

 the American Anthropologist (November). It appears that, in 

 a general way, white children present more diversity, negro 

 •children more uniformity, in all their normal physical characters. 

 This becomes gradually more marked as age increases. As to 

 physical abnormalities, those of congenital origin are much less 

 frequent in the negro child than in the white one. With 

 acquired abnormalities, principally the result of rachitic condi- 

 tions, the case is almost the reverse, those characters being less 

 frequent in the white children. 



A RECE.VT number of tlie Arheihn aus deni Kaiserlichen 

 gesundheilsamt contains a series of reports drawn up by medical 

 ■officers resident in different parts of German East Africa. These 

 reports are furnished in response to a circular issued by the 

 Colonial Medical Department, containing a list of various sub- 

 jects upon which it was desired to collect information. Amongst 

 these we find vaccination, the surgical treatment of various 

 wounds, ic, the treatment of mental diseases; whilst special 

 attention is directed to the collection and identification, where 

 possible, of herbs and roots employed for medicinal purposes by 

 the natives. As a result of this circular an immen.se amount of 

 most valuable and instructive information has been collected, 

 which not only should prove of use, but is also of great interest 

 NO. I 52 I, VOL. 59] 



from an historical point of view, throwing as it does considerable 

 light on the social conditions of these natives. Some curious 

 medical superstitions are recorded, such as the treatment of 

 stings from scorpions by burning the sting of the insect and 

 placing its ashes on the wound ; whilst, in the absence of this 

 remedy, salt and snuff are to be rubbed in ! The mentally 

 afflicted suffer most from the effect of superstition, however, and 

 have to submit to what can only be described as the most cruel 

 torture to procure the ejection of the evil spirit with which the 

 patient is believed to be possessed. The perpetuation of the 

 race does not seem to be regarded as of much importance, 

 and in the case of one tribe when twins are born, one is 

 always destroyed, usually the last born, except where both sexes 

 are represented, under which circumstance the female is in- 

 variably sacrificed. Nothing but praise can be accorded to the 

 enterprising spirit of the German Colonial Department, which 

 is not alone ambitious to extend its dominions, but is equally 

 concerned in obtaining all the information it can about the 

 po.ssessions which it has already acquired. 



Among the subjects of papers read at the recent conference 

 of the Society for the Protection of Birds, was the decrease in 

 the numbers of swallows and martins coming to this country, 

 by Mr. J. H. Allchin. One of the causes of this decrease is 

 that swallows are netted by the thousand as they came to the 

 shores of Italy in their northward migration, and are eaten as 

 food ; they are also caught in great numbers with artificial flies 

 and fish-hooks ; all this being contrary to the Italian law and 

 to treaty with the European Powers, which binds Italy not to 

 permit the netting of birds on her shores. As regards destruc- 

 tion of swallows on the southern coast of France, records in 

 official publications testify to the massacre of millions, while on 

 their passage, by means of the net, the fish-hook, and the electric 

 wire. The chief disturbing element in England is the common 

 house sparrow, which persecutes the house martin, ejecting it 

 from its nest, and destroying eggs and young. Mr. Allchin 

 proposed that the Society should present a strong protest to the 

 Governments of Italy and Fr.ance against the destruction of birds 

 in the course of their annual migrations, and should also petition 

 the Board of Agriculture to send a protest to the aforesaid Govern- 

 ments, on the ground that the destruction of the Hirundinidae 

 and other insectivorous birds was diminishing their numbers to 

 such an extent as to lead to a serious increase of insects injurious 

 to our crops. He further suggested that means should be taken 

 to destroy the eggs (but not the nests) of house sparrows, and 

 that County Councils be petitioned to place all swallows and 

 martins and their eggs on the protected list, and to extend 

 the close season to the full extent of the birds' stay in this 

 country. 



Dr. Tollenaar, writing from Batavia with reference to the 

 alleged momentary increase of temperature in one end of a bar 

 of metal suddenly cooled at the opposite end, calls attention to 

 the fact that the matter was investigated sixty years ago by 

 Schroder in a paper entitled " Kaun die plotzliche Abkiihlung 

 eines Theiles einer erwarmten metallische Masse eine plotzliche 

 Temperatursteigung eines anderen Theiles zur Folge haben ? " 

 (Pogg. Ann. ,^6, p. 135.) In our correspondence columns will be 

 found a letter (p. 174), in which it is stated that there is no 

 increase of temperature in the bar when one end is cooled. 



Dr. G. Ercolini contributes lo Xhe Atti dei Lincei {v'li. $) 

 a note on the variations produced in the dielectric constant of 

 glass by mechanical traction. The experiments, which agree 

 with those of Quincke, serve to verify Lipmann's theory that the 

 dielectric constant of glass increases with traction. The greater 

 the tension the more closely is the increase in the constant 

 proportional to it ; at first it falls short of proportionality. 



