For two or three years past Mr. David Bruce, in S. W. Colorado, has been taking Papilio Bairdii in company with a very different form, P. oregonia, as we have called it, and also with the form I described recently as P. Hollandii, which last is in general like Bairdii, but has the abdomen either with a broad stripe of yellow or almost completely yellow, instead of spotted yellow in rows, as in the Asterias group, and as in typical Bairdii.