2 LAMKLLICOKMA. 



as follows : " Sexual selection, which implies the possession of consi- 

 derable perceptive powers and of strong passions, seems to have been 

 more effective with the Lmnellicorns than with any other family of 

 beetles. With some species the males are provided with weapons for 

 fighting ; some live in pairs, and show mutual affection ; many have the 

 power of stridulating when excited ; many are furnished with the most 

 extraordinary horns, apparently for the sake of ornament ; and some, 

 which are diurnal in their habits, are gorgeously coloured. Lastly, 

 several of the largest beetles in the world belong to this family, which 

 was placed by Linnaeus and Fabricius at the head of the order." It does 

 not, however, appear to be proved that any insects select their mates 

 from any regard to personal appearance ; in fact, in the case of the 

 Lepidoptera the female evidently exercises no choice in the matter as far 

 as has at present been observed, and until it be proved that insects act 

 in this matter as mammalia and birds undoubtedly do, the hypothesis of 

 the horns of the Lamellicornia being ornaments gradually developing 

 from sexual selection does not seem to be a sound one ; at present, how- 

 ever, their use has not been explained. 



This series of Coleoptera, as above mentioned, includes most of the 

 largest beetles in the world, notably the great Goliath beetles, and 

 others which nearly equal them in size ; several authors have proposed 

 to place them at the head of the whole order, partly on the ground of 

 their size and development, and partly, in some cases, because of their 

 internal structure ; the question, however, requires very careful con- 

 sideration, and in the present state of our knowledge it is far better not 

 to disturb the existing arrangement. 



The larvm of the Lamellicornia are thick and fleshy ; the head is corneous and 

 rounded, without ocelli ; the maxillae are composed of two lobes, which are either 

 free or connate ; the antenna? are inserted at the sides of the head on a projection 

 which looks like a first joint; the joints vary in number from three to five; the 

 thoracic segments are of about the same length as the abdominal segments, and do 

 not differ from them much in character ; the latter are nine in number, occasionally 

 ten ; the anal segment is as broad as the preceding, and is in many cases divided in 

 the middle by a transverse furrow, so that it appears as if divided into two joints ; in 

 the greater number of species the abdominal segments from the first to the seventh 

 are divided into three raised folds or " bourrelets," which unite at the sides in a 

 triangular tubercle bearing one of the stigmata ; of these latter there are nine pairs 

 in all, the first situated on the sides of the prothorax, and the eight others on the 

 fine eight abdominal segments, all on each side lying in the same horizontal line ; 

 the legs are rather long, with the tarsi very small or completely wanting, in which 

 case the tibiae bear a minute claw at apex, which, however, is often absent at least on 

 the posterior legs ; the apex of the body is curved, so that the insect is not capable 

 of walking on a flat surface ; these larvae feed on vegetable substances and dung, 

 but occasionally on animal matter ; those that live in wood or at the roots of plants 

 and grass take three years or more to come to maturity, whereas the coprophagous 

 species go through their metamorphoses in a very short time (<. Chapuis et Can- 

 deze, Cat. des Larves des Coleopteres, p. 112 115) 



Erichson divides the larvae of the series as follows: 



