ii6 ANTS. 



and (|ucenlcss colonies. ]n artificial nests Wasmann, Miss Fickle and 

 myself have found egg-laying workers in abundance. 



Xo\v as the males that develop from worker eggs are perfectly 

 normal, and in all probability as capable of mating as those derived 

 from the eggs of queens, we are bound to conclude, especially if we 

 adopt the theory of heredity advocated by Weismann himself, that the 

 character.- of the mother (in this case the worker) may secure repre- 

 sentation in the germ-plasm of the species. Weismann is hardly con- 

 sistent in denying the probability of such representation, for when he 

 is bent on elaborating the imaginary structure of the germ-plasm he 

 makes this substance singularly retentive of alteration by amphimixis, 

 but when he is looking for facts to support the all-sufficiency of natural 

 selection the germ-plasm becomes remarkably difficult of modification 

 by anything except this eliminative factor. Certainly the simplest and 

 directest method of securing a representation of the worker characters 

 in the germ-plasm would be to get them from the worker itself that 

 has survived in the struggle for existence, rather than through the 

 action of natural selection on fortuitous constellations of determinants 

 in the germ-plasm of the queen. If we grant the possibility of a 

 periodical influx of worker germ-plasm into that of the species, the 

 transmission of characters acquired by this caste is no more impossible 

 than it is in other animals, and the social insects should no longer be 

 cited as furnishing conclusive proof of Weismannism. 



Plate has attempted to overcome the difficulties presented by the 

 normal sterility of the worker by supposing that the distinguishing 

 characters of this caste arose prior to their inability to reproduce. 

 He recognizes the following stages in the phylogeny of the social 

 insects : 



" i. The presocial stage with but a single kind of male and female. 



" 2. The social stage with but a single kind of male and female. 

 The peculiarities in nesting, caring for the brood, and other instincts 

 were already developed during this stage. 



" 3. The social stage with one kind of male and two or several 

 kinds of females, which were all fertile, but in consequence of the 

 physiological division of labor became more and more different in the 

 course of generations. The division of labor took place in such a 

 manner that the sexual functions passed over primarily to a group A, 

 whik- the construction of the nest, predatory expeditions and other 

 duties devolved mainly on another group of individuals (P>), which 

 on that account used their reproductive organs less and less. 



" 4. The present stage with one kind of male, a fertile form of 



