4 PREFACE TO THE 



proper to consider the relation which this kind of alterna- 

 tion bears to that with which we have hitherto been 

 acquainted, as taking place in the propagation of the 

 lower forms of animals ; and this I have done in the last 

 Chapter (V) of the Essay. It appears to me very evi- 

 dent, that these preparative generations, all of which have 

 this in common that they are invariably produced from 

 ova, without being themselves oviparous, that they are all 

 of the same sex, and all eliminate an offspring from the 

 germs contained within them, which offspring in course 

 of time becomes the animal from which the preparative 

 generation had derived its existence, and that all, as it 

 were, eliminate this progeny by their vital powers and 

 by means of their bodies ;* it is evident, I say, that these 

 generations represent in a lower degree what we have so 

 long admired in the gregarious insects, or those which 

 live in colonies, such as the Termites, Ants and Bees, &c., 

 because the precedent, ^preparative generations, are, in 

 these instances, in consequence of the complete abortion 

 of the sexual organs, converted into preparative broods, 

 and the " nursing" (ammen), which in the lower animals 

 is performed within or by the bodies of the •' nursing" 

 individuals, is for the same reason, in the above-named 

 class of insects performed differently, being in them 

 represented by a " fostering" of the young (Brutpflege) 

 to the performance of which duty the " feeders" are 

 impelled by an artificial instinctf or conscious exertion of 

 the will, and of M^hich they are rendered capable by the 

 peculiar formation of certain organs, at the expense of 



* On which account I have termed these generations " nursing generations" 

 (ammende), and the individuals of ■which they are constituted " nurses" {am- 

 men). [Though the word "nurse" in English does not exactly correspond 

 with what the author intends to convey by the word " amme" (a wet-nurse), 

 yet the translator has thought that the use of this short word, till a better 

 expression be devised, might be excused, not on the score certainly of its 

 elegance, but because it more nearly corresponds with the meaning of the 

 original than any other Enghsh word which suggests itself to him, and that 

 by makiag use of it a constant periphrasis is avoided.] 



t Kunsttrieb, the instinct to produce certain compound effects resembling 

 those of human art. 



