680 APPENDIX B. 



covered and carried home, are carefully packed away and hypno- 

 tized by a sting, so that they may live until the growing larva 

 has need of them. For all these proceedings there have to be 

 provided the fit external organs cutting instruments, <fcc., and 

 the fit internal organs complicated nerve-centres in which are 

 located these various remarkable instincts, and ganglia by which 

 these delicate operations have to be guided. And these special 

 structures have, some if not all of them, to be made perfect and 

 brought into efficient action before egg-laying takes place. Ask 

 what would happen if the reproductive system were active in 

 advance of these ancillary appliances. The eggs would have to 

 be laid without protection or food, and the species would forth- 

 with disappear. And if that full development of the reproduc- 

 tive organs which is marked by their activity, is not needful until 

 these ancillary organs have come into play, the implication, in 

 conformity with the general law above indicated, is that the per- 

 fect development of the reproductive organs will take place later 

 than that of these ancillary organs, and that if innutrition checks 

 the general development, the reproductive organs will be those 

 which chiefly suffer. Hence, in the social types which have 

 descended from these solitary types, this order of evolution of 

 parts will be inherited, and will entail the results I have inferred. 



If only deductively reached, this conclusion would, I think, be 

 fully justified. But now observe that it is more than deductively 

 reached. It is established by observation. Professor Riley, 

 Ph.D., late Government Entomologist of the United States, in 

 his annual address as President of the Biological Society of Wash- 

 ington,* on January 29, 1894, said : 



" Among the more curious facts connected with these Termites, because of 

 their exceptional nature, is the late development of the internal sexual organs 

 in the reproductive forms." (p. 34.) 



Though what has been shown of the Termites has not been 

 shown of the other social insects, which belong to a different 

 order, yet, considering the analogies between their social states 

 and between their constitutional requirements, it is a fair infer- 

 ence that what holds in the one case holds partially, if not fully, 

 in the other. Should it be said that the larval forms do not pass 

 into the pupa state in the one case as they do in the other, the 

 answer is that this does not affect the principle. The larva 

 carries into the pupa state a fixed quantity of tissue-forming 

 material for the production of the imago. If the material is 

 sufficient, then a complete imago is formed. If it is not sufficient, 

 then, while the earlier formed organs are not affected by the 

 deficiency, the deficiency is felt when the latest formed organs 

 come to be developed, and they are consequently imperfect. 

 * Proceedings of the Biological Society of Washington, vol. ix. 



