On the basis of these experiments it is concluded that temperature has a major effect of the longevity and survivance of the of Black soldier fly Hermetia illucens and is probably a major factor in the distribution of this insect in North America. Of course it is likely that other ecological factors also will affect the spread of Black soldier flies or that a combination of these factors may be involved. It is believed, on the basis of these laboratory experiments, that in areas of the country where low temperatures, the Black soldier fly will not be a serious problem.