OLD AND NEW METHODS IN ZOOLOGY. 25 



of varied colors and sizes, the insects issuing from which are wing- 

 less. When the trial is made, they will be found incapable of 

 reproducing the warts they came from ; they are, besides, all fe- 

 males. Again, we may see, in the spring, the ends of the limbs of 

 the same oak bearing greenish-red tumors, which naturalists have 

 long called oak-apples. They are also galls from which Cynips 

 issue; these too, like the others, are incapable of reproducing 

 the swellings from which they came ; but they have wings, and 

 are both male and female. Here, then, are beings totally different, 

 if we study them separately as they come out from their nests. 

 Now let us follow the experimenter, first observing that the insect 

 of the root has been called Biorhiza, and that of the apple Texas. 

 The Biorhizas escape from the roots on which they are hatched, 

 and raise themselves up slowly and painfully, having no wings, 

 to the ends of the branches of the tree. There they lay unfer- 

 tilized eggs, and cause, by piercing the twigs, the oak-apples from 

 which the Teras issue. On the other side, the Teras, escaping 

 from their apjjle, copulate, and the fertilized female descends to 

 deposit her eggs in the roots. The Biorhizas, therefore, are 

 hatched from the eggs of the Teras, and the Teras from the eggs 

 of the Biorhizas. Here, then, are two genera wholly distinct in 

 habits, organization, and external characters, which are neverthe- 

 less derived each from the other, and which zoologically ought to 

 form only one. How could M. Adler have discovered these facts, 

 except by experiment ? When we remark that the Cynips are 

 relatively high in the animal scale, we are justified in believing 

 that a very great number of similar surprising facts may yet be 

 found among lower forms. 



I can not refrain from relating another life-history which is 

 almost a romance. There is a hard sandstone in Provence, inter- 

 spersed with friable strata, in which burrowing insects construct 

 their chambers. A kind of bee, the Anthophorus, makes nests 

 there and fills them with honey, on which it leaves its egg to float ; 

 then, finally, plasters up its chamber. Instead of Anthophores, 

 entirely different insects come out from these nests Sitaris, be- 

 longing to a group very remote from the bees. Let us see how 

 they manage to substitute themselves for the legitimate proprietor 

 of the nest. In the autumn the impregnated female of the Sitaris 

 deposits her eggs in front of the sealed galleries of the Anthopho- 

 rus. The young are hatched from these eggs, and lie in front 

 of the closed doors, and thus remain in a mass, mingled with the 

 dust and rubbish of the place, through the winter. In the spring, 

 such of the bees as have reached their term come out from their 

 prison. These earliest insects are all males ; but, though preco- 

 cious in being hatched, they are still tender to the changes of the 

 weather, and remain half frozen and torpid in the dust along with 



