LUMINOUS INSECTS. 515 



and pupa states, there seems nothing inconsistent in the fact of some light 

 being then emitted, with the supposition of its being destined solely for use 

 in the perfect state : and the circumstance of the male having the same 

 luminous property, no more proves that the superior brilliancy of the 

 female is not intended for conducting him to her, than the existence of 

 nipples and sometimes of milk in man proves that the breast of woman is 

 not meant for the support of her offspring. We often see without being, 

 able to account for the fact, except on Sir E. Home's idea, that the sex of 

 the ovum is undetermined 1 , traces of an organisation in one sex indisputably 

 intended for the sole use of the other. 



I am, &c. 



i Phil. Trans. 1799, 157. 



LL 2 



