In all the males the patches were diffuse, that at the apex almost coalescing with the border. In the 3 from chrysalides exposed fourteen days these patches were connected by a narrow dark band (very different from the broad band of the females), occupying the same position as the clouding of the normal male, but blackened and somewhat diffused. In the 4 examples from the twenty-day pupæ, this connecting band was scarcely as deeply coloured and continuous as in the other 3. Beyond this change on the submarginal area, whereby a band is created where naturally would be only the two patches, and a slight clouding of the intervening fulvous surfaces, there was no difference of the upper surface apparent between these examples of both sexes, and a long series of natural ones placed beside them. On the under side all the males were of one type, the colours being very intense. There was considerably more red, both dark and pale, over the whole surface, than in a series of natural examples in which shades of brown and a bluish hue predominate. No change was observed in the females on the under side. It appears that fourteen days were as effective in producing changes as a longer period. In fact, the most decided changes were found in the females exposed the shorter period. It also appears that with this species cold will produce change if applied after the chrysalis has hardened. The same experiments were attempted in 1878 with pupæ of _Grapta Comma_. They were put on ice at from ten minutes to six hours after forming, and subjected to a temperature of about 0°-1° R. for eighteen to twenty days, but every pupa was killed. Chrysalides of _Papilio Ajax_ in the same box, and partly exposed very soon after pupation, were not injured. It was for this reason that none of the _Interrogationis_ pupæ were placed in the box till six hours had passed. It appears further that cold may change the markings on one part of the wing only, and in cases where it does change dark or dusky markings melanises them; or it may deepen the colours of the under surface (as in the females of the present experiment). The females in the above experiment were apparently most susceptible to the cold, the most decided changes having been effected in them. The resulting butterflies were all of one form, although both might have been expected to appear under natural circumstances. _Dr. Weismann’s remarks on the foregoing experiments._--The author of the present work has, at my request, been good enough to furnish the following remarks upon Mr. Edward’s experiments with _G. Interrogationis_:--