STATES «r INSECTS. 301 



and elytra, while the giant female has no vestige of either, 

 having the upper surface of its body naked and membra- 

 nous a . The species to which this illustrious Naturalist 

 here alludes, does not appear to have been ascertained. 

 The female of many gall-insects [Cocci) is so large in 

 comparison with the male, that the latter traverses her 

 back as an ample area for a walk b . But this is nothing 

 compared with the prodigious difference between the 

 sexes of Termes fatale, and other species of white ants, 

 whose males are often many thousand times less than the 

 females, when the latter are distended with eggs c . Acci- 

 dental differences in the size of the sexes sometimes arise: 

 as when the female larva has, from any cause, been de- 

 prived of its proper supply of food, it will occasionally be 

 less than the male. De Geer has stated a circumstance 

 with respect to the Aphides that produce galls, that 

 should be mentioned under this head — the first, or mo- 

 ther female, is larger than any of her progeny ever be- 

 come d . 



The second observation that may be generally applied 

 to the sexes of insects is, that, size excepted, there is a 

 close I'esemblance between them in other respects. But 

 to this rule the exceptions are very numerous, and so im- 

 portant that it is necessary to specify examples of each 

 under distinct heads. 



i. In some species the sexes are either partly or wholly 

 of a different colour. Thus, in the order Coleoptera, the 

 elytra of the male of Rhagium meridianum F. are testa- 

 ceous, and those of the female black. Leptura rubra of 



* Reaum. iv. 30. b Ibid. t. iv./. 15. 



c Sec above, Vol. II. 36. d De Geer iii. 25. 



