ME. &. LEWIS ON JAPANESE LANaUEIIDiE. 359 



of the elytra of the female ; the elytra at this part are slightly 

 corrugated, and the attrition thus caused must materially assist 

 the movements of the male. The bent tibise with apical teeth 

 (fig. 5) also aid the male at this time, when the legs would be in 

 active motion backwards and forwards, and help to support it 

 while gaining the necessary position. This is seen in two speci- 

 mens I haye gummed the one over the other ; and we can also see 

 from these specimens that were these modifications extended to 

 the fore tibiae, which are always simple, the structure would be 

 of no practical value. 



It is a matter of great significance to me that the parts in the 

 appendages of the male most used — parts which in an inorganic 

 substance would be most worn — are the parts where additional 

 tissue centres and forms additional structures, because it is a 

 striking instance of the uniform action of nature, creating in the 

 tibiae of the Languriidse parallel modifications to the enlarged 

 muscles of the blacksmith, or the armature of the Copro- 

 pliaga and other insects. The Gopris, in boring its holes, would 

 wear away its horn, if the increment of tissue did not tend to 

 enlarge and build up that part. If it is said that any individual 

 modification in the parent during, or close on, the act of congress 

 would influence the off"spring but little, as the elements of the 

 future animal must then be in a state when modification is almost 

 impossible, still, I think, that little is enough to be a great factor 

 in time. And I would call to mind the fact that in all in- 

 sects the time of sexual excitement is the time of the greatest 

 physical effort and bodily exertion, and that even in the shortest- 

 lived animals these efforts are continually made without affecting 

 the female, as when possession is attempted by two males. This 

 exercise is also observed sometimes (when the female is absent) 

 between two males. We may be sure that it is when an insect 

 is most active that modification of parts proceeds most rapidly, 

 rather than in the passive time of hybernation or in the quietude 

 of rest ; for inert animals, such as Starfish, which live in w^ater 

 of considerable depth, where the temperature and general envi- 

 ronment remain for long periods without change, can be traced, 

 almost in their present form, back into geological times. Any 

 modification, too, arising during hybernation would be more likely 

 to be a chemical than a physiological change, and we could not 

 conceive any reason for such modifications which might thus arise 

 being useful to, or in accordance with, the habits of the species. 



