HYMENOPTERA. 289 



make a noise with its jaws, which is answered by other indi- 

 viduals."^ 



Order, Hymenoptera. — That Inimitable observer, M. Fabre,"' in 

 describing the habits of Cerceris, a wasp-like insect, remarks that 

 "fights frequently ensue between the males for the possession of 

 "some particular female, who sits an apparently uncon'cerned be- 

 "holder of the struggle for supremacy, and when the victory is 

 "decided, quietly flies away in company with the conqueror." 

 Westwood" says that the males of one of the saw-flies (Tenthre- 

 dinae) "have been found fighting together with their mandibles 

 "locked." As M. Pabre speaks of the males of Cerceris striving 

 to obtain a particular female, it may be well to bear in mind 

 that insects belonging to this Order have the power of recognizing 

 each other after long intervals of time, and are deeply attached. 

 For instance, Pierre Huber, whose accuracy no one doubts, sep- 

 arated some ants, and when, after an interval of four months, 

 they met others which had formerly belonged to the same com- 

 munity, they recognized and caressed one another with their 

 antennffi. Had they been strangers they would have fought to- 

 gether. Again, when two communities engage in a battle, the 

 ants on the same side sometimes attack each other in the general 

 confusion, but they soon perceive their mistake, and the one ant 

 soothes the other.™ 



In this Order slight differences in color, according to sex, are 

 common, but conspicuous differences are rare except in the fam- 

 ily of Bees; yet both sexes of certain groups are so brilliantly 

 colored — for instance in Chrysis, in which vermilion and metallic 

 greens prevail — that we are tempted to attribute the result to 

 sexual selection. In the Ichneumonidss, according to Mr. Walsh,™ 

 the males are almost universally lighter-colored than the females. 

 On the other hand, in the Tenthredinidae the males are generally 

 darker than the females. In the Siricidse the sexes frequently dif- 

 fer; thus the male of Sirex juvencus is banded with orange, 

 whilst the female is dark purple; but It is difficult to say which 

 sex is the more ornamented. In Tremex columbEe the female is 

 much brighter colored than the male. I am informed by Mr. F. 

 Smith, that the male ants of several species are black, the females 

 being testaceous. 



In the family of Bees, especially in the solitary species, as I 



" Houzeau, 'Les Facultes Mentales,' &c. Tom. i. p. 104. 



=» See an interesting article, 'Tlie "Writings of Fabre,' in 'Nat. Hist. 

 Review,' April, 1862, p. 122. 



^' 'Journal of Proc. of Bntomolog. Soc.' Sept. 7th, 1863, p. 169. 



■is P. Huber, 'Recherohes sur les Moeurs des Fourmis,' 1810, pp. 150, 

 165. 



59 'Proo. Entomolog. Soc. of Philadelphia,' 1866, pp. 238-239. 

 20 



