Molt induction in lobsters (Homarus americanus) by intramuscular injection of ecdysterone triacetate

Summary The principal component of the successful, molt-inducing ecdysterone acetate mixture was established as ecdysterone triacetate and shown to have the same activity as the acetate mixture. The triacetate induced ecdysis in male lobsters collected in winter and summer and in female lobsters collected in winter. Intramuscular injections of triacetate in ethanol were as effective as those with oil emulsions.We thank Dr A. G. McInnes and D. Smith of the Atlantic Regional Laboratory, N. R. C., Halifax for obtaining the NMR-spectrum.