A Laboratory Comparison of the Toxicity as a Contact Poison of DDT with Nicotine, Derris Products and the Pyrethrins

Abstract
The toxicity of DDT as a contact spray under laboratory conditions has been tested on a number of insect species. The particulars of the species used are set out below. The toxicity of the DDT spray was compared in every instance with nicotine. A rotenone or derris suspension was included in the tests on Myzus cerasi, Phaedon cochleariae, Pieris brassicae, Pteronus ribesii and Phymatocera aterrima, and a pyrethrin spray in the tests on Pieris brassicae, Pteronus ribesii and Phymatocera aterrima.