The elaborate experiments of Schröder with _Abraxas grossulariata_ are difficult to follow and are complicated by the fact that the series which was submitted to abnormal temperatures was derived from an abnormal original pair. From the evidence given it is not clear to me whether the temperature had a distinct effect. This insect, like _Arctia caja_, produces an immense number of variations (especially in the amount of the black pigment) and as most of these are, I believe, reared in domestication for sale, it is highly probable that the species is easily influenced by cultural conditions. Schröder describes two other experiments which have been accepted by Semon and other supporters of the view that acquired characters are transmitted. In the first, _Phratora vitellinae_, a phytophagous beetle living on the undersides of leaves, was used. It naturally feeds on _Salix fragilis_, a species without a felt, or tomentum, on the underside of the leaves. Larvae were transferred to another willow (near _S. viminalis_) which has the undersides of the leaves felted. The larvae took readily to the new food, pushing the tomentum before them as they gnawed the leaves. They came to maturity and when they were about to lay their eggs they were given a free choice between _S. fragilis_ and the tomentose species. The greater number of ovipositions, 219, took place on _fragilis_, and there were 127 on the tomentose bush, which we are told was six times as large as the _fragilis_. The larvae from _fragilis_ were next put on the tomentose species and reared on it. When they became imagines they were similarly given their choice, with the result that there were 104 ovipositions on the tomentose species and only 83 on _fragilis_. In the next generations there were 48 ovipositions on the tomentose and 11 on _fragilis_. Finally the fourth generation made 15 ovipositions on the tomentose and none on _fragilis_. The difficulty about such experiments is obviously that one has no assurance that the change of instinct, in so far as there is any, may not be a mere consequence of the captivity. It must, besides, be extremely difficult to arrange the experiment so that there is really an equal choice between the two bushes, when one stands beside the other. Przibram, in quoting this case, considers that as the tomentose bush was about six times as large as the _fragilis_, some indication of the relative attractiveness of the two may be obtained by dividing the ovipositions on the larger bush by six, but I imagine the matter must be much more complex.