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found dead with the head in its position of retraction, that is, not only 

 drawn in close ti) the thorax above, but completely bent under the 

 thorax just as \n tlie pupae of many Cerambycidae . It is capable of this 

 elsewhere unknown movement throu^^h the possession of the large mem- 

 brane between the head and the thorax. The specimen Dr. Leconte had 

 for examination was evidently in this position, for he makes no mention 

 of the membrane, which could not have escaped his eye had it not been 

 concealed within the thorax. The drawings of Curtis show it perfectly, 

 but it appears to have been overlooked by subsequent writers. This fact 

 explains also why so many have failed to appreciate the suggestion of a 

 subterranean career in the beetle's appearance, for with its head tucked 

 under its wing, as it were, the mighty and warlike H. annUus becomes 

 heavy, purposeless, even stupid in aspect. 



Mr. Sharp in an article in the Annals of the Belgian Soc for 1884 

 states, that having sot'tened a damaged specimen, he found, that upon 

 overcorning the resistance of the powerful muscles contained in the thorax, 

 he was able to make the head execute the complete movement of flex- 

 ion and contraction. Putting the head into its natural position, he was 

 able to inspect carefully the soft membrane thus brought to light. In 

 doing so he made the interesting discovery of the wound which had prob- 

 ably caused the death of the insect. That it had been inflicted during 

 the life of the insect, was conclusively proved by the dried serum sur- 

 rounding the wound: and, from the shape corresponding exactly with 

 the shape of the genal processes of the head, it was highly probable 

 that it had been inflicted by another individual with one of those parts. 

 Instances of combats between males for the possession of females are 

 known in many groups of animals, and even among man, so that there 

 is nothing improbable in Mr. Sharp's supposition that the wound he dis- 

 covered, was caused in such a combat. This, according to Mr. Sharp, 

 would explain the great development of their genal processes; and, 

 carrying out the theory of sexual selection, even the other characters. 

 The beetles in their combats would endeavor to wound one another in 

 the highly vulnerable soft membrane. An individual finding himself 

 worsted in the fight, would need all the strength of the powerful muscles 

 of contraction to hold his head close down to the thorax, and thus pre- 

 vent his opponent reaching the weak point in his chitinous armor. His 

 enemy on the other hand would use his mandibles to pry him open, 

 and bracing himself with his stout hind legs, the struggle would go on 

 until the weaker brother was defeated. Thus, according to Mr. Sharp, 

 the individual deficient in the peculiar weapons of offense and defense, 

 would often fail to secure a mate, and in the long run the majority would 

 leave no off'spring to perpetuate their failings: and in the series of ages 



