64 THE RING OF NATURE 



these cuckoo bees that enter their nests, and there 

 live and multiply at the expense of their hosts. 



There have at present been discovered only 

 four species of these cuckoo humble-bees, but as 

 the genus is well spread throughout the world, 

 and as these parasites usually very closely resemble 

 their hosts, it is likely that there are other dis- 

 coveries in store for some lucky or enterprising 

 entomologist. At any rate, the knowledge that 

 there are such beings adds to the interest with 

 which we daily watch the flowering currant bush. 



Apathus, unfeeling, is the name by which we 

 know this genus of humble-bee parasites. They 

 are generally to be known from the honest insects 

 they personate by their darker wings and more 

 shiny abdomen. By this latter characteristic the 

 bee-keeper knows those of his hive bees that have 

 taken to robbing their neighbours. He believes 

 that the defenders strip off some of the hairs of 

 the invaders in their struggles to prevent their 

 entrance. It is strange that a similar mark 

 should adhere by inheritance to these unchallenged 

 thieves of the humble-bee. 



As soon as the red dead-nettle is well in bloom 

 it is visited by another bee, obviously not of the 

 ' humble ' persuasion. It is when it first appears 

 a yellow-thoraxed bee, of a stoutness approaching 

 that of the class just mentioned, but of far livelier 

 habits, darting this way and that at speed and 

 hovering before a flower in a way that reminds 

 us of the humming-bird hawk-moth. When the 



