298 



(May, 



On February 15th, I observed two specimens of Cheiropachus face to face on a 

 piece of stick, their antennae, though bent downwards, 'as in the position of repose, 

 were in active tremulous motion, and the insects occasionally advanced so that those 

 organs touched. They frequently touched the wood also with their antennal tips ; 

 and, on looking closely, I saw a minute orifice in the bark, in which I soon made 

 out a pair of jaws working. Tliis hole was enlarged rapidly, and the head of a 

 Cheiropachus soon became visible. On the head emerging, the antennae of those 

 outside worked even more vigorously, and seemed to increase the eflforts of the 

 enclosed Cheiropachus to escape. 



On the thorax of the latter (which proved to be a female) appearing, it became 

 obvious that the two outside were sworn foes, each alternately edging the other oflf 

 for a little way, the antennse continuing vigorously working, and now all the time 

 touching the female. Suddenly the two males seized each other by the jaws, and 

 for a moment were quite still, just as the female completed her escape. The next 

 movement was so extremely rapid, that I could not see the details — the female 

 came out so quickly, that it appeared as if she would have got away ; but in an 

 instant one of the males completely disappeared, the other was seated on the back of 

 the female, and pairing had occurred ; the whole transaction having lasted less 

 than a minute, though possibly my observations disturbed them. Several other 

 specimens were close by, apparently males, whose size and strength were unequal 

 to a competition with the two in possession. I may remark that Cheiropachus is 

 able to leap a distance of nearly an inch. The above observations explain at least 

 one use of that power, and also that in a winged species of Chalcis pairing occurs 

 immediately on the exclusion of the female, as it is well known to do in some 

 apterous and partly apterous species. — Id. 



Discovery of a male Cynips. — Through the kindness of Mr. Darwin I have 

 received both sexes of a species of Cynips ; they were bred from the Black Oak 

 (Quercus spongijica) by Mr. Benjamin D. Walsh, the American Hymenopterist. The 

 gall from which the male and female {Cynips aciculata) were obtained is larger 

 than the bullet-gall of the oak so common in England, being two inches or more in 

 diameter. According to Mr. Walsh's observations the males are only obtained from 

 those galls which develope flies early in the season, two months before the great 

 autumnal brood appears ; the latter all being invariably of the female sex. Follow- 

 ing up this hint, we may hope this year to obtain males of Cynips lignicola, — 

 F. Smith, British Museum, IQth April, 1869. 



An early swarm of Formica nigra. — I was walking yesterday through the 

 Botanical Gardens here, when my attention was suddenly attracted by some winged 

 ants running up the glass of the Cactus-house. Many male and female specimens 

 were struggling in the webs of sundry gaunt, hungry-looking spiders. Upon 

 inquiry I ascertained from one of the attendants that they had begun to swarm 

 about the 2nd inst. Their nests seem to be situated close to the hot-water pipes, 

 which have maintained a temperature in the house, during the last two or three 

 months, of 60°— 65° Farenht. by day, and 55°— 60° by night. The attendant has 

 not been aware of the existence of the nests for more than a fortnight ; but, unless 

 memory fails me, this ant used to remain active all through tlie winter in the 

 neighbouring Palm-houso, which is scarcely, if at all, warmer. — A. E. Eaton, The 

 Union Society, Cambridge, April 9th, 1869. 



