132 



KNOWLEDGE. 



[June. 1901. 



Astronomical.— The observations of the total eclipse 

 of the sun on May 18 th ap]iear to have been only 

 partially sucL-essful. lu S\imatra the conditions were 

 very uufavoui'able, althouirh iii)t bail enough to completely 

 obscure the sun. We gather that the Dutch astronomers 

 succeeded in obtaining photographs both of the corona 

 and spectra, but the jnismatic camera did not succeed. 

 At the time of writing there is little news from the 

 British observers in Sumatra, but it has been reported 

 that the duration of totality was six minutes twenty-one 

 seconds. In Mauritius, where Mr. and Mrs. Maunder 

 were stationed, the total phase appears to have been well 

 observed. Fifty-two photographs of the corona and 

 eighteen photographs of the s[)ectruni were taken with 

 the various instruments. The corona was of the expected 

 minimum tyjje. 



Prof. Campbell has recently utilised the spectro- 

 scopic results obtained at the Lick Observatory for an 

 investigation of the sun's motion in space. The 

 conclusion is that the sun is approaching a point in ~R A. 

 277° 30'. Decl. + 19' 58', with a velocity of i;»-89 

 kilometres per second. Tliis velocity is considerably 

 smaller than the average of the 280 stars on which the 

 calculations are based, and Prof. Campbell further con- 

 siders that there is evidence that the faint stars are moving 

 more rapidly than the bright stars, and therefore that they 

 are relatively further from us than the investigations of 

 their proper motions have led us to conclude. Through 

 the generosity of Mr. Mills, Prof. Campbell will be enabled 

 to extend his researches so as to include stars invisible at 

 Mount Hamilton by establishiug an observatorv in the 

 Southern Hemisphere. 



Mr. R. T. A. Inues, of the Cape Observatorv, has 

 comnumicated a paper to the Royal Astronomical Society 

 in which he gives_ several instances of stars which have 

 not disappeared instantaneously when occulted by the 

 moon, some of them vanishing in two distinct stages, and 

 others by "gliding." He points out that on several 

 occasions double stars have been detected bv the phenomena 

 attending their occultations, and considers that dis- 

 appearance either in two stages or by gliding is almost 

 certainly due to the star being reallv a binarv^'system. A 

 particularly interesting feature of this mode" of detecting 

 double stars is that the observation can be made with 

 telescopes of very moderate size. Mr. Junes remarks that 

 many of the doubles which may in this way be discovered 

 will be too close for telescopic confirmation, and may 

 therefore form a class intermediate between visual doubles 

 and spectroscopic binaries. Special interest attaches to 

 the behaviour of known spectroscopic binaries, and it is 

 suggested that careful observations should be made of the 

 coming series of occultations of a Virginis. 



In the course of a communication received from Baron 

 Kaulbars, of St. Petersburg, it is suggested that the 

 fluctuations in brightness of Nova Persei are due to a riog 

 of meteors, of varying density, which surround the star. 

 The idea seems to be that the light is dim when a dense 

 portion of the ring is in front of the star, and bright when 

 a sparse portion is in front. The arrangement appears to 



be a very artificial one, and it is difficult to understand 

 how it can account for the changes of spectrum. 



In Harvard Circular No. 58, Prof. Pickering discusses 

 the interesting photometric problems suggested by the 

 variability of Eros. Owing to the varying position of the 

 observer with regard to the planet, it will be possible to 

 gain mucli information which is inaccessible in the case of 

 a variable star. The material already accumulated is 

 under discussion, and the preliminary results will shortly 

 be available for publication. In the photographs taken 

 in 1893, 1894, and 1896 (before the existence "of the planet 

 was known), distinct changes can in some cases be traced 

 ill the brightness of different parts of the same trail. 

 This suggests an easy method of discovering short period 

 variability in an asteroid. — A. F. 



Botanical. — A curious instance of a root being 

 transformed into a leaf, or, at least, into an organ which 

 apparently possessed all the usual characters of a leaf, is 

 recorded by Professor R. A. Philippi in a recent number 

 of the Berichte der deulschen bofaiiischen Oesellschaft. 

 Professor Philijjpi planted in flower-pots a number of 

 corms of Crocus rernus, which he had received shortly 

 before from Holland. These failed to show any signs of 

 growth above the soil, which was therefore turned out of 

 the pots, when a white piece of root, 12 cm. long and 

 2 mm. thick, was found attached to a piece of a Crocus- 

 corm. He inserted the conn-end of the root in soil to the 

 depth of 4 cm , and allowed the rest to be exposed to the 

 light. After several weeks, a slightly elevated line was 

 observed on the side of the root which received the greatest 

 amount of light, and this quickly developed into a green, 

 leaf-like body, 7 mm. in width. The function of assimila- 

 tion j)roceeded as in an ordinary leaf. New. roots were 

 formed, and subsequently four normal leaves. — S. A. S. 



ENTOMOLOGiCAL.^An interesting contribution to the 

 life-history of beetles has been made by Mr. G. C. 

 Champion and Dr. T. A. Chapman, who publish in the 

 Trans. Entom. Soc. London, for 1901 (pp. 1-18, pis. 1-2), 

 some observations on certain species of Orina, an Alpine 

 genus of Leaf-beetles (Chrysomelida;), adorned with 

 brilliant metallic colours. The statement of former 

 naturalists that most of these insects bring forth their 

 grubs in an active state is confirmed ; such " viviparity," 

 unusual in insects generally, is especially rare among 

 beetles. One of the observed species (0. /ci's/i^), however, 

 lays eggs which are subsequently hatched. The most 

 remarkable fact brought to light in this ptaper is that, 

 in O. viHifjera at least, the embryos develop not in the 

 vagina but in the ovarian tubules. Evidently the method 

 of fertilization in these beetles must be exceptional. 



Father Wasmann describes (Zeits.f. iriss. ZooL, LXYII., 

 1900, pp. 599 — 617, pi. 33) some remarkable flies — Ternii- 

 toxenia — found in the nests of South African termites 

 (" white ants "). These flies have the hinder segments of the 

 swollen abdomen doubled under, somewhat like the "tail" 

 of a crab, and the thorax is provided with appendages 

 (suggestive of vestigial wings) whereby the insects are 

 lifted and carried aliout by then- hosts. This observation 

 renders it likely that the flies supply the termites with 

 some food-product, despite the fact that the lancet-like 

 structure of their jaws shows them to derive their own 

 food from the bodies of the termite larvfe. They furnish, 

 therefore, an interesting link between the parasitic and 

 the inquiline habit. — G. H. C. 



Zoological. — In a paper on the musk-oxen of Arctic 

 America and Greenland, published in a recent issue of the 

 Bulletin of the American Museum of Natural History, Dr. 



