92 INSECTS ABKOAD. 



earlier days of Entomology the two sexes were set down as 

 different species. 



Then, in these Beetles a still furtlier pecnliarity is fonnd ; 

 namely, the great variation in size of the males, and the differ- 

 ence in shape as well as in size of their jaws. It often happens 

 that two males are found in the same locality, and that one of 

 them will be at least four times as large as the other, while the 

 jaws of the smaller specimen shall be comparatively small and 

 feeble, and without the bold teeth and knobs which arm that of 

 its larger relative. It is conjectured that this difference in size 

 and development is caused by insufficient food during the larval 

 state, as is known to be the case with some other insects, but the 

 reason for the constant appearance of this arrested development 

 in the Pectinicornes is not very easy to see, 



Owing to their great size and remarkable development of jaw, 

 this group of insects has always attracted attention. Dr. Thos. 

 Mouffet, in his "Theatre of Insects," written about the year 

 1620, has a quaint description of Beetles belonging to the 

 Lucanida? : — 



" Beetles are some greater, some less. The great ones, some 

 have horns, others are without horns. Those that have horns, 

 some are like Hart's horns, others like Goat's horns. Others 

 have Bull's horns ; others have ram's horns ; some have horns 

 on their nose : we shall speak of them all in order. 



" The Platycerus, or Hart's-horn Beetle, is called Lucanus by 

 Nigidius, as Pliny witnesseth. Some call it the Bull, others the 

 Plying Stag. , . . Amongst all the horned Beetles, for the shape 

 of its body, length, and magnitude, it may challenge the first 

 place, and is the most noted. It is blackish, of a dark red, 

 especially about the outward cover and the breast. It hath two 

 whole horns without joynts, and with haunches like a stag, as 

 long as our little finger in such as are grown up, but they are 

 less and shorter in the young ones : or (as Pliny saith) it hatli 

 long and moveable horns nicked with cloven pincers, and ^hen 

 it will it can bite or nip with them. 



"Por it will close them wilfully, and useth its homes for that 

 end for which crabs and lobsters do their clawes. The eyes are 

 hard, putting forth, and whitish : it hath fore-yards on both sides 

 of them, one pair that are branched between the homes and the 

 eyes, the jnynt thereof making almost a right angle, and two 



