196 TITK entomologist's RECORD. 



but the queen, having a plentiful supply of food, develops large 

 oviducts (some 200 tubes in the bee), whilst the worker, with a smaller 

 supply of food, is not stimulated in this direction, the oviducts being 

 reduced (to about 6 in the bee) whilst the secondary structures 

 connected therewith are more or less atrophied. The special characters 

 of the worker, such as the pollen bags, &g., are structures that require 

 but little food or material for their development, hence the smaller 

 size, ill-developed ovaries, &c., all point to the fact that the smaller 

 supply of food has affected the final development of the worker, 

 especially as we know that it might have been — had it been fed on 

 more nutritious food from the tliird day onward — a queen instead of 

 a worker. 



No one denies that the difference of food does end in producing the 

 results described ; it is the way in which this acts that is in question, 

 although Darwin in the Origin of Species attempts to explain the origin 

 of neuters among social insects without reference thereto. Tlie 

 Lamarckian considers that the action of the food is direct ; the 

 Darwinian, that chance tendencies in the direction of the present 

 workers proving to be advantageous in the advancement of the 

 community, the tendency Avas seized upon, and as it was found to be 

 more or less in the power of the community to govern it in the required 

 direction, it was developed accordingly. 



Professor Weismann says that food is not the cause of the develop- 

 ment but merely the stimulus to which the organism reacts in the 

 given direction ; that the cause itself is the variation in the germ, that 

 the germ-plasm of each egg has in it in fact three different parts or 

 "ids," a male-id, a queen-id, and a worker-id ; that absence of ferti- 

 lization is the factor that determines the development of the male-id, 

 whilst fertilization determines the development of the female-id; and that 

 when the latter has been determined the queen-id or worker-id is 

 developed under the stimulus of good or poor feeding respectively, 

 and that all modifications are due to the latent primary constituents 

 of which tliese " ids " are assumed to be composed. 



According to the Professor's explanation, then, the germ-plasm 

 of every bee's egg has in it all the constituents necessary to form 

 a male, a queen or a worker, and either of these " ids " may be 

 developed by means of a proper stimulus. He further asserts tliat each 

 of these " ids " is in turn composed of the jjrimary constituents of 

 which the different parts of the body are built up. These primary 

 constituents he calls " determinants," and as each different part of the 

 body is subject to variation, he supposes the determinants to have been 

 developed by minute variation of the germ-plasm by the process of 

 selection. Criticising this part of Professor Weismann's paper Dr. 

 Mivart says: — *' He (the Professor) appears to feel no difficulty in 

 believing that in the germ-plasm of a bee's egg, there are not only all 

 the necessary constituents or determinants of a queen, a worker and a 

 drone, all three ready to be called forth into predominance by an 

 appropi-iate stimulus, but also that all these have been exclusively 

 developed by fortuitous minute variation in the structure of the germ- 

 plasm of an insects (the hypothetical root-ancestor of the bee) in the 

 idants, ids, and Vnophors of the ancestors of which there was never 

 anything whatever of the kind I And not only the diverse conditions 

 of the ovary and all the positive characters of which males, queens and 



