LK 



this connection with his want of knowledge as to what in this domain has been 

 investigated, discussed, and refuted by many entomologists, other than English, 

 which, naturally, entails a very limited judgment on the subject. He thus 

 arrives at the following ten propositions, which I will quote here. 



1. The cases of resemblance between distinct kinds of insects are very 

 numerous — too numerous to be accidental. 



2. These resemblances are to a very great extent independent of affinity. 

 Some of the most striking are those between insects of different orders. 



3. They are peculiarly liable to occur in insects of the female sex. 



4. They are, speaking generally, found only between the inhabitants of 

 the same region. 



5. They may affect one phase of a seasonally dimorphic insect differently 

 from the others. 



6. No structure or detail of organisation is involved in these resemblances 

 exept in so far as a modification therein may assist in producing a superficial 

 likeness in aspect or behaviour. 



7. In the production of these resemblances the same effect is often brought 

 about by different means. 



8. Every transition exists between a likeness which is so remote as to be 

 fairly disputable, and a resemblance which may even deceive a skilled observer. 



9. In some cases there may be great disparity in point of numbers 

 between the forms linked together by community of aspect. In other cases 

 the numbers may be nearly equal. 



10. The combinations of two or more forms resembling- one another are 

 in many cases not isolated, but are often connected with other combinations 

 by a more or less complete series of gradations. 



Dr. DixEY calls these facts, but it is clear that they are not facts in a 

 scientific sense ; they are purely propositions recapitulating what according to 

 his notion appears to result from^ certain observations; propositions, whose 

 accuracy is not only considerably to be discounted, but which, moreover, are 

 of far too uncertain and subjective a character to allow scientific — /. e. logical — 

 conclusions to be deduced from them. But this course is not adopted by 

 Dr. DixEY. He simply proceeds to discuss the theory of geogrophical influ- 

 ences, the artist theory of Mr. Abbott H. Thayer, and the opinion that these 

 resemblances are to be attributed to internal causes, winding up with the decla- 

 ration that he associates himself with the opinion of Bates and Fritz Muller. 

 But while his arguments against the artist theory contain a great deal of truth, 

 this much cannot be said, as regards the remainder. His reasoning practically 

 consist of a priori adducing the well known Darwinian theories of utility and 



