^84 



KNOWLEDGE 



Dkchmber, lyil. 



A PRIMITIVE ANT SOCIETY.— There isaMediterraneau 

 ant, Aphacnogasfer sardoa by name, not uncommon in 

 Sardinia, which illustrates a simple type of societary form. — 

 simple, at least, as ant-societies t;o. It has been recently 

 studied by Dr. Krause-Heldrungen. who describes the way in 

 which the ants huddle together in living balls, interlocked with 

 mandibles and tarsi, and holding the eggs, larvae, and pupae 

 in the centre, kw average society consists of three hundred 

 to a thousand individuals ; the males have not been found : 

 and the observer found only one queen. .Architectural con- 

 struction is at a minimum : they use holes in the ground. 

 They do not store and they have no guests. Huddling 

 together in a ball is their form of sociality. In winter the 

 ball is very stiff and is slow to rela.x when it is unearthed. 

 In summer, naturally, it is more plastic, being made a?id un- 

 made several times .i day. 



BL(JOD-SL'CKING .MAGGOTS. — There is a fly called 

 Auchmcroiiiyiit Intcola (Eabr.l, whose larvae have the 

 remarkable habit of piercing the human skin and sucking 

 blood. This has been hitherto a quite unique thing, but 

 E. Koubaud has found its parallel in a related .African form, 

 for which he establishes a new genus Choeroiuyia. One 

 species lives in the burrows of the Cape .Ant-Eater and 

 another along with the Wart-hog. The flies eat dung and like 

 darkness. The larvae live in the damp ground ; they are able 

 to fast for a long time : they are attracted to the warmth of 



their hosts ; they fix themselves on the skin, pierce it, and suck 

 blood. They can ingest three times their weight of blood, 

 Koubaud reared one on himself. 



BEETLES IN NESTS.— Heinrich Bickhardt has collected 

 the available information in regard to what he calls " nidi- 

 colous " beetles — those which live in the nests of birds and 

 mammals. There are no fewer than twenty-eight which are 

 found exclusively in nests. A much longer list is given of those 

 that usually occur in nests, but also in other suitable places 

 Besides these there are casual visitors. Of the e.xclusively 

 nidicolous beetles, eighteen are confined to the homes of 

 Mammals, such as mole, hamster, mouse and rabbit : seven 

 are confined to the nests of birds, such as dove, sand-martin, 

 owl, and woodpecker : three are found associated with both 

 birds and mammals. 



INNERVATION OF WINGS IN LEPIDOPTERA.— 

 R. Vogel has made a study of the rich innervation of the 

 wings in butterflies and moths, and shows how rich the wings 

 are in sensory structures. There are tactile scales and 

 (probably) tactile spines. There are peculiar papillae, which 

 may have to do with orientation in flight, and " chordotonal 

 organs " like those which distinguish notes in various 

 Orthoptera. .Altogether the wing is an exquisitely sensitive 

 structure. 



SOLAR DISTURBANCES DURING OCTOBER, 191 1 



Bv ER.\XK C. DENNETT. 



The falling oft' in solar disturbance shown last month was 

 equally noticeable during October. Observations were made 

 on twenty-nine days, the omissions being on the 16th and 27th. 

 On fourteen days the disc presented an even brilliance, save 

 for the delicate granulation, these being October the 9th. 10th, 

 13th until 15th, 17th until 21st. 24th. 2rith. and 28th until 31st. 

 On the 1st and all other dates after the Kith only faculic dis- 

 turbances were seen. The central meridian on October 1st 

 was 289° 42'. 



No. 37. — Two brilliant cur\ed ridges of f.iculic matter 

 formed a striking object a little within the eastern limb of the 

 Sun on October 1st, like the borders of an elliptical disturb- 

 ance. On the 2nd in place of the western ridge a dark spot 

 having two umbrae had developed, whilst three pores were 

 embedded in the eastern ridge. Next morning the spot had 

 become 10.000 miles in diameter, and the number of pores had 

 reached seven, the group being 30,000 miles in length. Only 

 two of the pores were seen following the leader on the 4th. 

 By the 6th the leader enclosed two umbrae, whilst one pore 

 showed 10.000 miles behind and a second nearly two degrees 

 south of the leader. On the Sth the leader, reduced to a pair of 

 umbrae, was alone, and had quite disappeared before next 

 morning. The spectroscope showed a considerable amount of 

 activity around this group indicated by dark hydrogen flocculi 



extending for a long distance. On the 6th there was a consider- 

 able prominence visible, projected on the bright surface, a little 

 south-east of the spot, whilst the whole region showed traces 

 of helium by the presence of the dark line known as D:i. 



The dotted areas indicate the positions of faculic 

 disturbances. On October 2nd a small bright knot was 

 visible near longitude 353°, S. latitude 17°. On the Sth 

 there was a small knot at 269°, N. latitude 5 . On the 11th 

 and 12th two separate faculic disturbances were visible near 

 the western limb, one double group closely ahead of the place 

 where the spot group. No. 37, had disappeared, whilst the 

 other was on the other side of the equator. On the 22nd and 

 23rd there was a faculic district about longitude 10°, and 10° 

 N. latitude. On the 25th there was a group of greyish pores 

 in a disturbed area near longitude 2S0°, but careful measures 

 were not possible. 



The Prominences are much fewer in number than was the 

 case only a few months since. The most remarkable one 

 appears to be a very tall spindle at 20 South-east, seen on 

 October 21st. 



Our chart is constructed from the combined obserxations of 

 Messrs. John McHarg. ,\. A. Buss. E. I". I'eacock and 

 F. C. Dennett. 



n.AY OF OCTOBER, iqii. 



W X 'J! 'i bO' TtS 80' W lOO' 110' li'ff IM I4(r I5(f 160' 170' 180' 190' aiO' lid HS ZiO' 240 25|J 1^ ZTS 2S0' SOT 300" M' 320 35tf M' 350' 5«' 



