64 ENTOMOLOGICAL NEWS. [Feb., 'lO 



which are strongly and more or less roughly sculptured, these 

 two extremes being connected by an unbroken series of inter- 

 mediates in degree of sculpturing. 



It happens that the type specimen which served for Say's 

 description, takes its place in the middle of the series and it is 

 therefore mesotypical of the specific aggregate; the extremes 

 being respectively the forma glabra and forma interstitialis of 

 the present list. 



The individuals making up the specific aggregate do not 

 necessarily breed true to any intraspecific degree of sculp- 

 turing, as this is wonderfully influenced by environment and 

 food supply. It has been observed that those individuals that 

 develop in an exposed, open or dry region, where the body 

 fluids are reduced to a minimum by evaporation during the 

 closing chapters in the ontogenesis, especially after casting of 

 the pupal skin, will develop a feeble or a comparatively smooth 

 form of sculpturing; on the other hand, those individuals de- 

 veloping in a moist, shaded or protected region or area, where 

 the body fluids are conserved and abundant, evaporation be- 

 ing reduced to a minimum, will have the integuments and ely- 

 tral apodemes after the casting of the pupal skin, well dis- 

 tended by the body fluids and the punctures and striae rela- 

 tively deepened and more or less fixed in that condition during 

 the hardening of the exoskeleton. In this way a more strongly 

 punctured or strongly striate form is produced ; rapid evap- 

 oration of the body fluids at this time tends to produce a 

 wrinkling of the elytral wall. 



It is to be borne in mind that any given geographical area, 

 small or large, will have relatively dry and warm, moist and 

 cold conditions co-existing in different sections of that area. 



These data have been noted by my colleague. Dr. E. C. Van 

 Dyke, as well as by myself in the field and laboratory. 



The individuals that constitute the specific aggregate, there- 

 fore, are only those which really belong to a single species and 

 will breed true within the limits of normal specific variation. 

 The development of smooth and rough forms depending more 

 upon meteorological conditions than anything else, nanoid 



