60 



coloured hairs. Each of the ungues has a httle tuft of strong hairs issuing from the extremity of the 

 terminal joint of the tarsi. 



Female. This sex is unfurnished with horns. The elytra are the same colour as in the male, not 

 spotted so much, if at all, and more rugose. Thorax black, with a few yellowish spots, foraied like stars 

 or rays on it. In other respects it resembles the male. 



Drury adds to this insect the following remark — " I have observed many species of 

 beetles whose males have been furnished with horns, either on the head or thorax, but in 

 which the females have none, but have those parts quite smooth and plain ; and my obser- 

 vations incline me strongly to think that this rule subsists in every one of them, through 

 the whole class. The instances I could bring in support of this opinion are too many to 

 be admitted in this place." 



The circumstance observed upon in the preceding note is certainly very interesting in a 

 physiological point of view. In quadrupeds we find both sexes of cornuted species armed 

 with horns ; but in insects almost universally the males alone are provided with these 

 appendages. It is also worthy of remark, that although in the majority of insects the 

 females considerably surpass the males in size, yet in those species in which the males are 

 cornuted, the females are almost invariably smaller than their partners. 



Burmeister lays it down as a rule, that with regard to the differences of the sexes, their 

 whole character may be thus distinguished ; viz. that the male displays a preponderance of 

 evolution, and the female a preponderance of involution ; and observes, " that some beetles 

 have processes upon the head and thorax, which, like the mandibles, can meet, like tongs, 

 and thus serve as a weapon. This is asserted of Hercules and its large comrades." This 

 opinion as to the uses of these horns can, however, scarcely be maintained, since the number 

 of species in which the horns really meet is very few. Kirby and Spence observe, " ^ATiat 

 may be the use of these extraordinary appendages to the males, has not yet been ascer- 

 tained. Whether the individuals of this sex are more exposed to the attack of birds and 

 other enemies, in consequence of being more on the wing than the females, and are there- 

 fore thus provided wath numerous projecting points of defence, is a question worth 

 considering." It is also to be observed that these appendages, instead of being deciduous, 

 as in many of the higher animals, are in insects component parts of the external skeleton. 



There are a few exceptions to the observation of Drury ; thus in the Lamellicorn 

 genus Hoplites Dej. Catal. (Scarabseus Pan,) the females are cornuted as well as the males ; 

 and in the genus Osmia, belonging to the section of wild bees, Dasygastres, Latr., the females 

 alone have the head furnished with two porrected horns. 



