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Since I first catalogued our species ofBombyciæ, under Herrich-Schæffer's later designation ofCymatophorinæ, in the Proc. of the Entomological Society of Philadelphia for May, 1863, there have been but few additions to the group. Nor have the then debatable points been settled. The validity ofexpultrixas a "species" is still doubtful.doi:10.4039/ent13151-7 fatcat:7g3pd3nnunfivmfkrt2xrrys7a