214 THE ENTOMOLOGIST. 



the Entomological Society on March 4th, 1908, which opinion I was 

 at once certain that I had never expressed, because it was one which 

 I never held, viz. that "the close affinity with M. dictynna made 

 separation superficially very difficult, and until all forms were reared 

 from the ovum it would be impossible to determine whether hrito- 

 martis constituted a separate species or not." I observe that Dr. 

 Chapman guards himself by saying that I am " reported as saying " 

 so, but on looking up the reference, I see that even this is hardly the 

 case ; no quotation marks are used, and it may quite well merely 

 represent the impression left on the mind of the secretary. I am 

 well aware that I am to blame in the matter, as I never supplied the 

 secretary with notes as to what I did say, but I cannot too forcibly 

 repeat that this is an opinion which I never for a moment held, 

 though I consider it very important that all forms should be bred 

 from the ovum. What my real views on the matter are is set forth 

 in the following paragraphs.] 



It would seem to be the peculiar snare of the specialist, or 

 at least of those who have made a long and detailed study of 

 any one organ, that they are apt to magnify the importance of 

 the special object of their study, and to regard it as the standard 

 by which everything is to be measured, to the exclusion of other 

 structures which may in numerous instances be of greater 

 significance. One of the most unfortunate consequences of this 

 tendency of human nature is that those who have not specialized 

 in the same direction are apt to lose sight of the real value 

 which often underlies exaggerated claims, just as one instinc- 

 tively (and often quite wrongly) rejects for all purposes the 

 patent remedies which profess to effect universal cures. Yet it 

 would probably be impossible to make a careful and detailed 

 study of any organ without discovering facts which were of some 

 biological value, or which were in some cases of use for purposes 

 of classification, and with regard to the genital armature this is 

 peculiarly the case. But, as with all other structures, the 

 knowledge acquired on this subject cannot stand alone, and it 

 will often rather afford hints as to the directions in which further 

 search should be made, than supply students with the means 

 of delivering infallible judgments on questions of phylogeny or 

 classification. Although it is always possible that similarity of 

 structure may be reached along different lines of evolution, yet 

 this will always be the exception and not the rule, so that 

 similarity in these structures will always be prima facie evidence 

 for close relationship, and identity will be still stronger evidence 

 in the same direction, and, unless contradicted by other facts, 

 will argue strongly in favour of identity of species ; but before 

 such identity can be assumed, other circumstances must be 

 taken into consideration, or wrong conclusions are likely to be 

 reached. 



Now it so happens that in this comparatively small group 

 two cases occur which illustrate this fact somewhat remarkably ; 



