V P.RENTHIDAE AGLYCYDERIDAE 297 



the body, although this itself is so drawn out as to he quite 

 exceptional in the Insect world : ^ the antennae are inserted 

 near the tip of the rostrum instead of near its base, as they 

 are in the female. The size of the males is in these cases usually 

 much larger than that of the female." The males of some species 

 fight ; they do not, however, wound tlieir opponent, but merely 

 frighten him away. In Eivpsalis it appears that the rostrum 

 of the female is apt to become fixed in the wood during her 

 boring operations ; and the male then extricates her by pressing 

 his heavy prosternum against the tip of her alidomen ; the stout 

 forelegs of the female serve as a fulcrum and her long body as a 

 lever, so that the effort of the male, exerted at one extremity of 

 the body of the female, produces the required result at the other 

 end of her body. The New Zealand Brenthid, Lasiorhynchus 

 harbicornis, exhibits sexual disparity in an extreme degree : the 

 length of the male is usually nearly twice that of the female, and 

 his rostrum is enormous. It is at present impossible to assign 

 any reason for this ; observations made at the request of the 

 writer by Mr. Helms some years ago, elicited the information 

 that the female is indefatigable in her boring efforts, and that 

 the huge male stands near by as a witness, apparently of the 

 most apathetic kind. 



Coleoptera of uncertain position. 



There are three small groups that it is impossible at present 

 to place in any of the great series of beetles. 



Fam. 84. Aglycyderidae. — Tarsi three-jointed, the second 

 Joint lohed ; head ■not ^'''olonged to form a beak. The two most 

 important features of Ehynchophora are absent in these Insects, 

 while the other structural characters are very imperfectly known, 

 many parts of the external skeleton being so completely fused 

 that the details of structure are difficult of appreciation. West- 

 wood considered the tarsi to be really four-jointed, but it is not 



^ In the males of the genus Ccdeocera the tips of the elytra are drawn out into 

 processes almost as long as the elj^tra themselves, and rivalling the forceps of 

 earwigs. 



- The stature of the individuals of the same species is, in some of these 

 Brenthidae, subject to extreme variation, especially in the males, some individuals 

 of which — in the case of Brcnthiis anchorago — are five times as long as others. 



