136 INSIiCTS AT HOME. 



on Woodcut XV*. Fig. 4, enlarged about two and a half dia- 

 meters, so as to show the peculiarities of its structure. 



The genus is distinguished by several points of structure. 

 The antennae of the male are beautifully and deeply pectinated, 

 the pectination being on the inner side only of the antenna?. 

 The head projects boldly from the thorax, thus differing greatly 

 from the preceding insect, and the ends of the mandibles are 

 two-notched. The body is rather long and moderately convex. 

 The ground colour of this insect is black, but when it is in 

 good condition, it is thickly covered with yellowish-grey 

 down, which has a sort of rich velvet-like aspect. Tlie elytra 

 are also covered with down, and are very soft. 



This description applies only to the male Beetle, the female 

 being so utterly unlike her mate, that few persons, even if 

 they had some acquaintance with entomology, would believe 

 her to be the female of the pretty little Beetle which has just 

 been described. Indeed, for a long time the two sexes were 

 regarded as two distinct insects, belonging even to different 

 genera, the male retaining the name of Drilus, and the female 

 being described under the title of Cochleoctonus vorax. The 

 name was appropriate enough, inasmuch as the word Cochleoc- 

 tonus signifies ' snail-killer,' and the specific name vorax was 

 given in allusion to its voracity. 



It is really no wonder that creatures so different in appear- 

 ance should be looked upon as two distinct insects. In the 

 first place, the female is inordinately larger than her mate, 

 who looks by her side — to borrow Keaumur's simile — like a 

 hare standing by a cow. A figure of the female is given on 

 Woodcut XV*. Fig. 3, where she is represented of the natural 

 size, i.e. about three-quarters of an inch in length. Now, the 

 male Drilus seldom exceeds one-quarter of an inch in length, 

 and often is below that measurement. Like the female glow- 

 worm, she is entirely wingless, but is more cylindric than 

 that insect, and the body is narrowed in front. The colour is 

 reddish-yellow, and each segment has two dark patches on the 

 upper side. Altogether, she is not a pretty insect — indeed, 

 she may almost be called ugly ; and how the slender, elegant 

 little male finds any attraction in such a huge, awkward-look- 

 ing mate, does certainly seem wonderful. 



The larva is very much like the female, but has a row of 



