212 KELLOGG AND BELL 



to the influence of the chromatic environment (larvae nearing 

 pupation acquire variously colored pupal cuticle depending 

 directly on the color of the immediate environment at the time 

 of pupation). The legs, antennag and mouth parts of insects 

 with incomplete metamorphosis may be influenced by use or 

 disuse, and perhaps in other direct ways, during the immature 

 life (post-embryonic development) of the individuals. These 

 insects have an exposed immature life like that of most other 

 animals and the variations apparent in their adult structures 

 may be and almost certainly are, in the case of certain charac- 

 ters partly adaptive, i. e.^ acquired. In this they differ, as also 

 do almost all other animals^ from the insects with complete 

 metamorphosis, of which we may say confidently that the vari- 

 ations exhibited by the adults in the case of numerous parts, 

 especially the wings, legs, antennas, mouth parts, eyes and the 

 spines, hairs and other processes of the body-wall as well as 

 the pattern and color of the body-wall, cannot possibly be 

 regarded as adaptive, i. e., acquired, but must be held to be 

 strictly blastogenic. 



Specific data of variations in various insects. 



Variation in Venation and Number of Hooks in Apis mellifica (the 

 honey bee).^ — The honey bee, Apis mcllijica, is an insect 

 with complete metamorphosis. The larvte are footless, soft- 

 bodied, white grubs which are born from eggs laid in the cells, 

 and which live for their whole life protected and cared for 

 in cells, those of any one community under identical conditions 

 of light and temperature and presumably of food and care. 

 Even those of different communities have practically an identi- 



1 Since the present account of our observations of the variation in the wings 

 of drones and worker honey bees was finished and made ready for the printer 

 a paper entitled " Comparative Variability of Drones and Workers of the Honey 

 Bee," by D. B. Casteel and E. F. Phillips has been published (Biol. Bull., Vol. 

 VI, December, 1903, pp. iS-37). It is of interest to compare the results thus 

 independently obtained by two pairs of observers. The general conclusion in 

 both cases is the same, viz., that the drones (parthenogenetically produced) vary 

 more than the workers (bisexually produced). In the absence of experimental 

 proof, the present writers are hardly willing to recognize the large importance 

 which Messrs. Casteel and Phillips give to extrinsic factors (depending on the 

 shape and size of the brood cells) in producing the drone variation. 



