Horned Beetles.^ 



589 



detaining an unwilling female. So far as our stag-beetle is concerned that was 

 a reasonable explanation, and it was backed by the assertion of some observers 

 that they had seen the great jaws so employed. The reason for its being reasonable 

 is that the jaws move freely in a horizontal plane, and can be used to hold a female 

 in their grip. But in many others the horns are more or less vertical in position, 

 and moreover are fixed outgrowths from the head and fore-body. The small amount 

 of movement possible to the head is not sufficient to be of anv \'alue in this con- 

 nection; whilst even if the tips of two horns of this sort could be brought together, 

 their polished and tapering ends would prevent the holding of anything between 

 them. A notable example of horns vertically opposed is seen in the Hercules beetle, 

 whose portrait is reproduced on page i. The well-known European rhinoceros- 

 beetle ^ — which, by the way, is not nearly so good a rhinoceros as some of the tropical 

 species of copris — illustrates the apparent uselessness of the horn by arching back- 

 wards from the front of the head over a scooped-out area of the fore-body ; and 

 there are many examples of a similar arrangement of these ornaments. 



Several of the photographs we give as illustrations show that, in most cases, 

 these growths do not offer suggestions of any way by which they could be useful, 

 either for holding females or for fighting other males for the possession of females. 

 It is true that the North American stag-beetle- is stated to use its horns in courtship, 

 and there seems no reason why our native species should not do the same. So 

 also might the splendidly armed chiasognathus (see page 4) of South America, 

 whose jaws exceed the combined length of head and bod}', and are set with sharp 

 teeth all along the inner margins — the fore-legs having a similar armament. This 

 beetle has the reputation of being pugnacious, and prone to open wide his jaws 

 in presence of a possible foe, but Darwin found on putting his linger betwee n them 



Photo by] [f. ^.'<•/•, F.r.s. 



Head of a Wood-boring Beetle. 



Ill this rxaiiipleof a honu fi beetle, the "horns" are due to a great development of the jaws. The aiiteiiiix also are so long and stout 

 that they merit the pojuilar term horns, so frequently applied to antenna-. The photograph is nearly four times larger than life size. 



' Oryctes nasicornis. 



* Cervus elephas. 



