438 ■ Transactions. 



arising from its extremity. The rostrum of the female is of a totally 

 difierent structure, with the antennae arising from its middle. Many 

 years ago Dr. Sharp, one of our greatest authorities on the Coleoptera, 

 was so impressed by the extraordinary sexual disparities exhibited by this 

 beetle that he wrote to the late Mr. Helms, at Greymouth, requesting him 

 to endeavour to find out something about the insect's habits. Mr. Helms, 

 who was then one of our keenest entomologists, replied that the female 

 Lasiorhynchus harbicornis is indefatigable in' her boring efforts, but that 

 the huge male stands by as a witness, apparently of the most apathetic 

 kind. I am not aware that later observers have elicited any further 

 information on this interesting subject. 



In addition to the above special examples it should perhaps be added 

 that some beetles are brilliantly coloured and have beautiful markings, 

 and nearly all are ornamented with elaborate sculpture. From a strictly 

 utilitarian standpoint it is difficult to see how such endowments are of 

 any direct benefit to the possessor in the ordinary struggle for existence ; 

 but if the principle of sexual selection be admitted the presence of such 

 elaborate adornments is quite intelligible. 



This completes the examples specially selected for the purpose of this 

 paper. It should perhaps be explained that other instances of the 

 operation of sexual selection could have been found, even amongst our 

 native insects, but it has not been deemed desirable to extend the paper 

 to an undue length. To those who have studied Part II in Darwin's 

 Descent of Man it will be iinnecessary to state that even more convincing 

 examples can be found amongst other classes of animals (notably birds), 

 and also in other lands. It may be safely said tliat sexual selection has 

 been a most powerful factor in organic evolution, operating in countless 

 instances wherever its progress has not been stopped by the more rigorous 

 principle of natural selection. Darwin clearly demonstrated that sexual 

 selection has taken a very prominent part in the evolution of man, and 

 there is no reason why its efiects should not continue in the future. That 

 a principle of such profound importance should receive so little practical 

 attention is indeed surprising. We constantly hear of the paramount 

 importance of education, and latterly we have heard a great deal about 

 the benefits of discipline and of physical training. Every naturalist knows, 

 however, that the effects of the most vigorous and successful training are 

 not inherited by the offspring of those who are trained : each generation 

 has to start to learn afresh. Not so, however, in the case of selection, 

 the effect of which is permanent. It is a fact of the highest certainty that 

 individuals possessing certain special attributes, if selected for breeding 

 purposes, will transmit those attributes to their offspring. Hence we can 

 see why the effects of sexual selection are so manifold throughout the 

 whole animal kingdom. 



