i^eb. 27, 1890] 



NATURE 



403 



In connection with the suggestion of the variability of the 

 spectrum, it is important to secure further observations. If the 

 existence of the bright line at some periods be established, we 

 may then safely conclude that the luminosity of the zodiacal 

 light is not entirely due to reflected sunlight. 



A. Fowler. 



Observations of C Urs^ Majoris and y3 Aurig.e.— The 

 periodic duplicity of the K line in the spectra of these stars before 

 noted (January 23, p. 285) led Prof. Pickering to conclude that 

 the time of revolution of the former system was 104 days. In 

 the current number of the Sidereal Messenger, however, Prof. 

 Pickering adds a note, dated January II, 1890, in which he 

 records that later observations make it probable that the period 

 of f Ursae Majoris is 52 days instead of 104, and that its orbit is 

 noticeably elliptical. The velocity of the components of j8 

 Aurigoe seems to be 150 miles per second, their period 4 days, 

 their orbit nearly circular, with a radius of 8,000,000 miles, 

 and their ma.sses 0"i or o'2, that of the sun being unity. 



Comet Brooks {d 1889). — The following ephemeris is given 

 by Dr. Knopf in Edinburgh Circular No. 5, issued on the 

 22nd inst. : — 



Decl. 



R.A. 



Decl. 



19 

 21 



23 

 25 



49 26 



53 17 



57 8 



o 59 



4 51 



8 43 



+ 20 8*o 

 20 25-3 



23 42 3 



20 59-1 



21 iS"6 

 21 31-8 



017, 



1890. 

 o , '• March. 

 + 17 58-6 I 15 .. 

 18 17-9 j 17 .. 

 18 369 



18 55-6 



19 141 

 19 323 

 19 50*3 ' 



The brightness on March i = o'24, and on March 25 

 that at discovery being unity. 



New Short-period Variable in Oi'Hiuchus. — Mr. Edwin 

 F. Sawyer announces the discovery that the star 175 {Uranome- 

 tria Argentina) Ophiuchi, R.A. I7h. 45m. 57s., Decl. - 6° 6'7 

 (1875*0), is a variable of short period {Astronomical yournal, 

 No. -210). The range of variation appears to be from 6 •2m. to 

 6*95m., and the period slightly greater than 17 days. 



Observations of the Magnitude of Iapetus. — In the 

 January number of Monthly Notices is found an interesting com- 

 munication to the Royal Astronomical Society by Mr. Barnard, 

 of the Lick Observatory, on the eclipse of this outermost satel- 

 lite in the shadows of the globe, crape ring, and bright ring of 

 Saturn. By frequent comparison of the light of Iapetus with 

 that of Tethys and Enceladus, the effect of the shadow of the 

 crape ring on the visibility of the satellite was tested, seventy- 

 five comparisons being made. It was found that, after passing 

 through the sunlight shining between the ball and the rings, 

 Iapetus entered the shadow of the crape ring. As it passed 

 deeper into this, there was a regular decrease in light until it 

 disappeared in the shadow of the inner bright ring. From the 

 observations it appears that the crape ring is truly transparent, 

 the sunlight sifting through it. The particles composing it cut 

 off an appreciable quantity of sunlight, and cluster more thickly, 

 or the crape ring is denser, as it approaches the bright rings. 



GEOGRAPHICAL NOTES. 



At the ordinary meeting of the Royal Geographical Society, 

 on Monday, Mr. C. M. Woodford read a paper on " Further 

 Explorations of the Solomon Islands." He has visited these 

 islands three times, and in the present paper he described what 

 he saw during his third visit, in 1888. He took up his residence 

 in the small island of Gavotu, off the coast of Gola, or Florida 

 Island, a place centrally situated for visiting Ysabel, Guadal- 

 canar, and other islands. He stayed with a trader named Lars 

 Nielson, who had since been killed and eaten by the natives, 

 as had also three of his boys. Since last June no fewer than 

 six white men had been murdered by the natives of the Solomon 

 Group, out of a total white population estimated at about thirty. 

 Mr. Woodford's principal object in his last journey was to 

 identify the places visited by the Spanish Expedition under 

 Mendaiia that discovered these islands in the year 1568. In this, 

 he thought he might say, he had been entirely successful. The 

 Spaniards related that when they were between Florida and 

 Guadalcanar they passed an island in the centre of which was a 

 burning volcano. This island was now conclusively identified 



with the Island of Savo. The lecture was illustrated with 

 photographs of natives of Guadalcanar and other places, as 

 well as specimens of rude architecture, by means of the 

 dissolving-view apparatus. 



According to the Copenhagen correspondent of the Frank- 

 furter Zeitung, an Expedition for the exploration of Greenland 

 will start next summer from Denmark. The plan of work has 

 been arranged by the Naval Lieutenant Ryder. The party will 

 consist of nine persons. They will have three boats, and a 

 steamer will convey them to the eastern coast as soon as the 

 condition of the ice will allow of a landing. It is proposed that 

 the region lying between 66° and 73° north latitude shall be 

 explored in the course of the summer, and that the party shall 

 push as far as possible into the interior. Sledges will be em- 

 ployed during the winter. The Expedition will be provisioned 

 and equipped for two years, at the end of which time the steamer 

 will return to take them away, cruising along the east coast till 

 they get down to the shore. The expenses have been estimated 

 at from 250,000 to 290,000 kroner (equal to from about ;^i 3,900 

 to ;^i6, 100), and the project is so popular, and looked on so 

 favourably by the Government, that it is practically certain that 

 the Diet will grant the money. 



The Geographical Society of Vienna issues a circular letter, 

 dated February 1890, announcing the election of officers made 

 last December. The new President is Herr Hofrath Ritter von 

 Hauer, Intendant des naturhistorischen Hofmuseums, 



LOCUSTS nV INDIA. 



I 



N 1889, parts of Sind, Guzerat, Rajputana, and the Punjab 

 were much troubled by locusts. A report on these de- 

 structive creatures is being prepared under the direction of the 

 trustees of the Indian Museum, Calcutta ; and, in the hope that 

 information about them, with specimens, may be obtained from 

 persons who have had opportunities of observing them, Mr. E. 

 C. Cotes, of the Indian Museum, has issued a preliminary note, 

 summing up some of the principal facts that have already been 

 brought together. This note is very interesting, and has been 

 compiled chiefly from the records of the Revenue and Agricul- 

 tural Department of the Indian Government. 



The generally received idea is that the locust which invades 

 India belongs to the species usually spoken of as Acriditim 

 peregi'inuvi, and supposed to have been the locust of the Bible. 

 The identity of Indian locusts has not yet, however, been defi- 

 nitely ascertained, and this is one of the points which require 

 elucidation. As far as we at present know, there seems reason 

 to believe that while Acriditim peregrimim extends its ravages 

 into the dry plains of the Punjab and Rajputana, the locust 

 which proved injurious in Madras in 1878, and in the Deccan in 

 1882-83, belongs to a very different species, which is probably 

 Acriditim sticcincttiin. In order to settle the question it will be 

 necessary to examine further specimens taken from destructive 

 flights which have appeared in various localities, the material in 

 the Indian Museum being at present insufficient. 



Dealing . with the natural history of locusts generally, Mr. 

 Cotes observes that all the different species which occur in 

 various parts of the world breed permanently in barren elevated 

 tracts where the vegetation is sparse. In years when they in- 

 crease inordinately they descend in flights from their permanent 

 breeding-grounds upon cultivated districts, where they destroy 

 the crops, lay their eggs, and maintain themselves through one 

 complete generation, but are unable to establish themselves per- 

 manently, usually disappearing in the year following the invasion, 

 to be succeeded, after an interval of years, by fresh swarms 

 from the permanent breeding-ground. 



Generally speaking, the life circle of a locust extends through 

 one year, in which period it passes through its various stages of 

 egg, young wingless larva, active pupa, and winged locust, 

 which dies after laying the eggs that are to produce the next 

 generation. The eggs are laid in little agglutinated masses in 

 holes, which the female bores with her ovipositor in the ground. 

 In temperate climates the eggs are usually deposited in the 

 autumn, but in sub-tropical countries, such as India, where there 

 is but little winter, the winged locusts live on through the cold 

 season, and only die off after depositing their eggs in the follow- 

 ing spring. In this case the eggs hatch after lying in the ground 

 for about a month. In both temperate and sub-tropical regions- 



