Some of these must be enumerated. The abdomen of the worker is comparatively short and rounded: that of the queen is larger and longer, and comes to a fairly sharp point. The jaws of the queen are notched on their inner cutting edge: the worker’s jaws are smooth like the edge of a knife. The tongue of the worker has a spatula at its extremity, and is furnished with sensitive hairs: the tongue of the queen is shorter, the spatula is smaller, while the hairs show greater length. The worker-bee has a complicated system of wax-secreting discs under the horny plates of her abdomen: in the queen these are absent, nor can the most elementary trace of them be discovered. In their nerve-systems the two show difference, the queen possessing only four abdominal ganglia, while the worker has five. The queen’s sting is curved, and longer than the worker’s: the sting of the worker-bee is perfectly straight. On their hind-legs the workers have a curious contrivance which bee-keepers have named the pollen-basket. It is a hollowing of the thigh, the cavity being surrounded with stiff hairs; and within this the pollen is packed and carried home to the hive. In the queen both the cavity and the hairs are absent. Her colour also is generally different from that of the worker-bee, her legs, in particular, being a much redder brown. Here is a problem for our great biologists—a problem, however, at which the plain, every-day man may well flinch. For we seem to have come face to face with new principles of organic life, facts incompatible with the accepted ideas of the inevitable relation between cause and effect. The irresistible tendency at this stage is to hark back; to repeat the experiment of the transposed eggs, and see whether no vital, initial circumstance has been overlooked. But the result is always the same. Nor can the most careful microscopical dissection of the eggs themselves reveal any differences. In this mystery of the structural variance between queen and worker, it would seem that we are forced to accept one of three alternatives. Either the egg contains two distinct germs of life, one developing only under the stress of hard times, the other only to the call of luxury. Or we must go back to mediæval notions, and believe that the worker-bees give or withhold some vital principle of their own during nurturing operations. Or we must give up the problem, and decide that creation works on lines very different from those on which we have hitherto grounded our faith.