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Show 1887.] VALUE OF COLOUR AND MARKINGS IN INSECTS. 217 exceedingly imperfect, while very perfect protection is gained in other ways. In fact I have suggested above that the species is not now "mimetic" at all, but retains two points of an ancestral condition in which it actually derived shelter from the reputation possessed by many Hymenoptera, these being (1) a structural point-its transparent wings, and (2) a habit-its diurnal flight. If this view be correct the species should be moved into the table given below of the results of experiments upon insects protected by evading their enemies, and there it would add to the instances which support Wallace's converse suggestion, that such insects will be found to be eaten just as tbe class we are discussing are generally refused. I have placed the species in the fourth table in deference to Wallace's opinion on the kindred species S. bombyliformis, which it closely resembles; but I believe that the place of both species should be below. I made several attempts to obtain the imagos of Sphecia apiformis, in order to offer these to m y Lizards; for this species certainly does suggest a stinging Hymenopterous insect in the most remarkable way ; but the attempt was unsuccessful. S. bembeciformis is equally well suited for experiment, but even more difficult to obtain ; I hope, however, to be able to experiment with one or both species in the course of next summer. It is noteworthy that (excluding S. fuciformis) there is probably no instance in this list which proves a difficulty in the way of Wallace's suggestion at all equal to that raised by the larva of D. euphorbia. For the pupa of A. grossulariata was not swallowed, but only well bitten by a very hungry lizard, and although the imagos of S. lubricipeda and P. auriflua were eaten (also by very hungry lizards in the former case), it cannot be asserted that they were eaten with relish; and, further, the experiment should be repeated with Birds and other species of Lizards. In all other cases the insects were refused by at least one of the animals to which they were offered. The comparison between the treatment received by Bees (described below) and Wasps, together with a comparison between their appearances, is strongly in favour of Wallace's suggestion. It now remains to analyze the list in the same manner as was adopted before, showing the transition of conduct observed (see Table, page 224). Comparing the three analyses of all experiments ever conducted upon presumably nauseous or dangerous insects, omitting S. fuciformis and including C. elpenor and C. vinula, we find that out of a total of 44 cases which have been tested 13 were entirely disregarded ; but this number includes P. machaon, which I believe ought to be placed below under forms chiefly defended by protective resemblances, and also S. menthastri (larvse, which were tasted in the youngest stages). Furthermore four species (including the two just mentioned) belong to Table III., containing larvse which can hardly be called conspicuous. Hence, omitting this table, the number is reduced to 9 cases out of a total of 37; and of the 9, not a single species has been offered to more than one out of the three groups of |