(Epicanta marginata, Fab.)
I can never look at this beetle without a feeling of emotion, for in a desperate struggle to escape from the fate predestined by a bald-headed ancestry, I once submitted to the treatment of a noted hair specialist and allowed him to apply to my scalp the acrid oil of the blister beetle. And the melancholy part is that it did no good.
Fabre has described how the female European blister beetle lays a thousand or two eggs in the ground in close proximity to the nest of the solitary bee whose eggs form the only food of the blister beetle larva. From the beetles’ eggs hatch out strong-jawed, six-legged spiny larvæ called triangulins. Although born close to the nests of the bees, which in this case are in the ground, these triangulins do not enter the nests, but attempt to attach themselves to any hairy object which may come near, much as burrs attach themselves to the wool of sheep.
A certain number of them by merest chance, apparently, succeed in getting onto the bodies of the bees and are carried by them to their nests. As the male bees, in this particular species, appear a month before the female, it seems probable, Fabre thinks, that the vast majority of triangulins attach themselves at first to the males and later, when a chance occurs, discovering their mistake, transfer themselves onto the females and so get carried to the underground cells, and are present when the mother bee fills the cell with honey and then lays an egg which floats around on top.
There is something ghastly in the picture of the mother bee laying her single egg, with the blister beetle larva on her back waiting till the last moment in order to slip unexpectedly from her body to the egg, on which it floats in the honey as on a raft. When the unsuspecting bee has closed in her unborn child, the hideous monster which is perched on top of it eats it up. This takes eight days, and when it has eaten up its raft, the triangulin moults and becomes, as it were, an aquatic creature with breathing pores so placed that it can float on the honey, and with a stomach so changed that it can be nourished by it. In about eight more days the honey is consumed and the final moult takes place.
A HIPPOPOTAMUS AMONG THE INSECTS
(Prionus sp.)