Anatomy of the Male Genital Tube in Coleoptera. 613 



We may conclude these very fragmentary observations 

 by pointing out that the diversity of the structures indi- 

 cates a considerable variety of functional detail. 



V. TAXONOMY AND PHYLOGENY. 

 Taxonomy. 



It has been supposed that the copulatory structures 

 are bad guides in classification, although they are generally 

 admitted to be of the first importance for the discrimination 

 of species. If, however, the extreme importance of the 

 genital conduit be seized, it will appear that its structure 

 must certainly be of very great assistance in taxonomy. 



We have in this memoir considered the male portion 

 only of the genital conduit, and that in a very imperfect 

 manner. It seems possible that if the female part of the 

 conduit were studied important distinctions would be 

 found therein. The only considerable contribution to this 

 subject we are acquainted with is the work of Stein (Mon. 

 Geschl., Organe, etc.). This was published sixty years 

 ago, and was not specially directed to the consideration of 

 the conduit, but so far as we can form an opinion from it, 

 and from our own limited observations and a few other 

 memoirs, the probability of important differences in the 

 female structures is confirmed. 



Under these circumstances it will be suggested that we 

 are not justified in making taxonomical generalisations on 

 the subject of the genital conduit at present. With that 

 suggestion we entirely concur. Nevertheless, as taxonomy 

 has been carried on with little or no consideration of this 

 important branch of anatomy, we think it important to 

 introduce this subject, notwithstanding the very incomplete 

 state of our knowledge. 



The generalisations that follow are, it will be seen, 

 imperfect and unsatisfactory. Possibly wider inquiry may 

 bring to light important distinctions we have failed to 

 appreciate, and it is also probable — we may say certain — 

 that such inquiry would reveal the existence of annectant 

 forms we are unacquainted with. As a further apology 

 for the following generalisations we may ask that it shall 

 be remembered that the other data of Coleopterous 

 taxonomy are also very incomplete. 



