38 DIFFERENCE OF THE SEXES. 



organs, or furnished with them of so small a size as 

 to be quite useless for the purpose of flight. This 

 deprivation of wings of course impresses a very sta- 

 tionary character upon the female, which has led 

 the worthy Swammerdam to hold up some of the 

 insects in which this distinction of the sexes occurs 

 as an excellent example to married couples, although 

 I must confess to a misgiving, that, however desirable 

 it may be that wives should imitate the quietness of 

 these wingless female insects, few ladies would wish 

 their husbands to adopt the vagrant habits of the 

 more fortunate males. The males of many insects 

 are also distinguished from the females by the greater 

 development, and even the altered form of the palpi 

 and antennse; the latter especially are very often 

 simple threads in the females, whilst in the males 

 they are pectinated (or comb-like), and sometimes 

 completely feathered by the emission of delicate fila- 

 ments from both sides of the joints. In some insects 

 the antennae of the males possess a greater number 

 of joints than those of the females. Besides these 

 characters, the legs of many insects differ in form in 

 the two sexes, the difference usually occurring in the 

 form of the tarsi. But whatever differences may 

 exist in the structure, and even in the appearance of 

 the two sexes of insects when mature, we shall find 

 that they agree most cordially in acting under an un- 

 controllable impulse implanted in them by nature, 

 the object of which is the fulfilment of the scriptural 

 injunction to " increase and multiply, and replenish 

 the earth." This, in fact, is the one impelling in- 

 stinct by which the actions of most mature insects 

 appear to be governed ; and so completely is this the 

 case, that few of them long survive the performance 



