62 PROBLEMS OF RELATIVE GROWTH 



TABLE IVa 



Anomma nigricans 



Data from Huxley and Bush (unpublished) 



Analysed in Huxley (1927) 



(1383) (165-3) 



176-0 223-7 



220-3 300-2 



272-7 427-6 



324-2 567-3 



367-5 661-9 



2 = 267 



k = about 1-55 (after first 2 points) 



x = abdomen-length 



y = head-breadth 



(in arbitrary units) 

 Figures in brackets ( ) indicate insufficient numbers in class. 



Camponotus gigas 



Data from E. Banks (unpublished) 



Analysed in Huxley (1927) 



x y 



75-0 9-6 



in-5 24-3 



241-0 82-0 



346-8 142-0 



S =357 



ft — about i-6 (after first point) 



x = total weight, mg. 



y = head-weight, mg. 



The obvious suggestion is that these series of workers and 

 soldiers do actually represent nothing more than a series of 

 size-forms of a single genetic type, possessing a mechanism 

 for heterogony of the mandible and head. The difference 

 from the other holometabolous cases hitherto considered is that 

 the absolute size-range is much greater, and that the differ- 

 ences in size can only be supposed to be brought about by 

 definite treatment of the larvae by their nurses, the largest 

 types being fed to the limit, the smallest types being deprived 

 of food, and so forced to pupate, while still quite small larvae. 

 That enormous differences in size may be produced by cutting 

 down or cutting off the food supply of insect larvae is estab- 

 lished through experimental work on blowflies (Smirnov and 



at very small absolute sizes, where the double-logarithmic curve is 

 distorted in the opposite sense, with concavity upwards : the meaning 

 of this, if not merely statistical, is unknown. 



