POLYMORPHISM IN NEUTER INSECTS 



63 



Zhelochovstev, 1926), housefiies (Herms, 1928), Drosophila 

 (Gause, 1931), etc. And the postulated differential treatment 

 of different worker larvae by their nurses is well within the 

 known range of complexity of ant behaviour (see also Emery, 

 1921). 



Fig. 36.- 



-Increase of relative size of head with absolute size of body in the 

 neuters of the ant, Pheidole instabilis. 



That the effect of size-changes may be differential is also 

 known ; e.g. Eigenbrodt (1930) finds that the increase of total 

 size in Drosophila caused by low temperature is accompanied by 

 a decrease in wing-size, which is somewhat greater for breadth 



