Chap. X. 
SEXUAL SELECTION. 
341 
CHAPTER X. 
Secondary Sexual Characters of Insects. 
diversified structures possessed by the males for seizing the females 
— Differences between the sexes, of which the meaning is not 
understood — Difference in size between the sexes lliysanura 
— Diptera Hemiptera — Homoptera, musical Dowers possessed 
by the males alone — Orthoptora, musical instruments of the 
males, much diversified in structure; pugnacity; colours — 
Neuroptera, sexual differences in colour — Hymenoptera, pugnacity 
and colours — Coleoptera, colours ; furnished with great horns, 
apparently as an ornament ; battles ; stridulating organs generally 
common to both sexes. 
Iff the immense class of insects the sexes sometimes 
differ in their organs for locomotion, and often in 
tlieir sense-organs, as in the pectinated and beauti- 
fully plumose antennae of the males of many species, 
hi one of the Ephemerae, namely Chloeon, the male 
has great pillared eyes, of which the female is entirely 
destitute . 1 The ocelli are absent in the females of 
certain other insects, as in the Mutillidce, which are 
likewise destitute of wings. But we are chiefly con- 
cerned with structures by which one male is enabled to 
Ampler another, either in battle or courtship, through 
|us strength, pugnacity, ornaments, or music. The 
innumerable contrivances, therefore, by which the male 
' :s able to seize the female, may be briefly passed over, 
besides the complex structures at the apex ol the abdo- 
men, which ought perhaps to be ranked as primary 
’ Sir J. Lubbock, ‘ Transact. Linnean Soc.’ vol. xxv. 1866, p. 484 
respect to tlie Mutillidae see Westwood, ‘ Modem Class, of Insects,’ 
Vo1 - ii. p. 213. 
