300 THE ENTOMOLOGIST. 



comprehensively dealt with than is possible in the pages of a 

 magazine. 



I have not directly replied to his other questions and 

 objections ; but Mr. Briggs will, I trust, pardon any seeming 

 discourtesy. The fact is, he has dealt too much in sarcasm and 

 too little in argument. It is really cruel of Mr. Briggs to expect 

 one to divest his observations of the ridicule in which they are so 

 closely enveloped, to ascertain the exact bearing of his queries 

 or the amount and quality of the evidence he has to offer in 

 support of his contentions. 

 October, 7th, 1887. 



[With the following note this discussion is now closed.] 



NOTE ON THE GENUS LYCjENA. 

 By J. Jenner Weiu, F.L.S., &c. 



I HAVE taken no part in the heated controversy over this 

 genus. The dispute appears to me to be one of words only. My 

 own views may be thus briefly sketched : — No two insects are 

 probably exactly alike. When a specimen exhibits a difference 

 from the normal type, such as may perhaps never occur again or 

 but rarel}'', this I take to be an aberration. Then there are 

 varieties constantly recurring, — often local varieties which may be 

 termed races ; such varieties insensibly pass into subspecies, and 

 these again into species. Some species may be closely allied, 

 such as L. icarus, L. bellargus, and L. corydon ; others less 

 closely allied to these, as L. cegon or L. astrarche ; others still 

 more remotely allied, as L. seiniargus, L. minima, and L. argiolus. 

 Boeticiis, often placed in the genus Lyccena, is the type of 

 Latreille's genus Polyommatus, and is even more remotely allied 

 to the species mentioned above. 



I trust none will deem me dogmatic when I state that in my 

 opinion, when three kinds of insects are found constantly existing 

 in each other's company, without crossing as a rule, they are 

 essentially species ; between these there is apparently a " physio- 

 logical " bar as Dr. Romanes has termed it, or amixia as it has 

 been termed by Professor Meldola in his translation of Dr. 

 Weismann's ' Studies in the Theory of Descent.' 



I cannot exjDect that all the readers of the ' Entomologist ' 



