BY JOHN WALTON. 9 



thereto a label numbered with red ink, exactly in the same 

 order as left by him, the names and red ink numbers put to 

 every insect, in regular order, as I took them out of the cabinet, 

 will afford greater facilities for examination, and prevent them 

 from being accidentally transposed or misplaced. 



The simple method which 1 adopted to identify the sexes of 

 S. tibialis, by means of oblong card boxes covered with glass, 

 I applied with equal success to many species of this genus. 

 I am aware objections may be raised against this plan, which I 

 shall not attempt to combat here : I will merely say, if the ex- 

 periments are conducted and watched with patience and atten- 

 tion, under a careful provision against all circumstances that 

 may create errors, by taking several pairs in coitu, and by a 

 close examination of the same, I have no doubt in my own 

 mind, the most sceptical person will be convinced of the identity 

 of the sexes ; at all events, there can be no mistake with the 

 males of species by this method, because they are seen with 

 certain organs, and observed in certain situations. Though I 

 may in many instances have succeeded, to the satisfaction of my 

 own mind, in uniting each sex to its legitimate partner, by this 

 method, yet I regard it only as a collateral aid in proving the 

 sexes. 



There are many important sexual characters more or less 

 developed throughout this extensive genus, and which I con- 

 sider of equal consequence with observing or taking them any 

 way in coitu ; these sexual characters are so conspicuously de- 

 picted, and so uniformly well defined, in the generality of the 

 species, that I have no hesitation in saying that an entomologist, 

 practically and familiarly acquainted with them, could at once 

 decide upon the sex of a species that he had never seen before. 

 I will now attempt to give an outline, and to describe generally, 

 as well as I can, and as the nature of the subject will permit, 

 the sexual characters of this genus. 



In my opinion, the sexual distinctions are so important to be 

 known, that no entomologist can acquire a correct knowledge 

 of all the species of this interesting genus without them : most 

 of the errors have originated for want of a better acquaintance 

 with the same. The extreme locality of some of the species, 

 and the great rarity of others, no doubt, has combined in 

 p. great measure to impede and retard our studies of these 

 characters. 



NO. I. VOL. V. c 



