Such a process is unknown outside the class of insects, and inside that class it is only known in a few of the two-winged flies.

Now, how "Natural Selection," or any "laws of correlation," can account for the gradual development of such an exceptional process of development--so extremely divergent from that of other insects--seems nothing less than inconceivable.

Mr.Darwin himself[37] gives an account of a very peculiar and abnormal mode of development of a certain beetle, the sitaris, as described by M.Fabre.This insect, instead of at first appearing in its grub stage, and then, after a time, putting on the adult form, is at first active and furnished with six legs, two long antennae, and four eyes.

Hatched in the nests of bees, it at first attaches itself to one of the males, and then crawls, when the opportunity offers, upon a female bee.

When the female bee lays her eggs, the young sitaris springs upon them and devours them.