Two specimens of this moth (Ocneria dispar, L.) were taken in Medford, Mass., last summer, which are what Ochsenheimer called perfect Hermaphrodites. One is much larger than the other, having an expense of 52 mm., and has the right half of the body, with the wings and antennæ of that side, of the form, colour and markings of the female, while the left side of the body, with its wings and antennæ, are male. The other example has a wing expanse of 39 mm., and is a male on the right side and a female on the left. In both specimens the frenulum is single on the male side, but divided on the female.