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Show 234 MR. R. SIIELFORD OX MIMETIC INSECTS AND [Nov. 4, are pronounced to be fully adult by tliat well-known authority on the Orthoptera., Mr. Malcolm Burr. Bearing in mind the errors made by Westwood and Duponcliel with regard to this insect, I made a careful search through the Sarawak Museum collection of Cicindelidae, and was rewarded by finding yet another example of this remarkable mimic placed amongst specimens of Tricondyla gibba (Chaud.), which it most closely resembles as regards size, coloration, &c. The specimen was smaller than those described above and is evidently a younger stage, but it differs in hardly any other way; and T. gibba, the model, also differs from T. cyanea var. wallacei principally in size (compare Plate X IX . figs. 3 & 4). A fourth specimen, of a very early stage, was taken in Kuching on the flowers of a flowering tree, frequented also by numerous insects of all orders, amongst others being the Cicindelid, Coilyris sarawakensis (Thoms.), which serves as a model to the young Condylodera (Plate X IX . figs. 5 & 6). At this stage, the insect is entirely dark blue, except the legs which are dark brown, and the greater part of the long antennae which are ochreous, the four basal joints only being blue. The prothorax shows no trace of the conspicuous puncturation of the adult, nor is it swollen as in the later stages, but more or less cylindrical like that of its model; the wing-rudiments are not yet visible, and the auditory organ on the fore-tibise can only be distinguished with difficulty. The model is somewhat larger, of a uniform dark blue with the legs dark brown. It is somewhat curious that the young Condylodera does not mimic Collyris emarginata (Macl.), a smaller species with red legs, especially since in the later stages it is red-legged species of Cicindelidae that are mimicked ; C. emarginata is, however, of a much more brilliant blue than any other Bornean members of the genus, or than the species of Tricondyla. This case of mimicry appears to me to be of exceptional interest and without a parallel. I have shown that Hymenopus bicornis, a floral simulator throughout the greater part of its life, mimics in its young stages the larvae of a bug; but I know of no ameta-bolous insect, except Condylodera tricondyloides, whicl i mimics different species of one family during the successive periods of its growth. iii. Mimic. Gryllacris n. sp. vicinissima nigratce (Br.). Plate X IX . fig. 8. Model. Pherop>sophus agnatus (Chaud.). Plate X IX . fig. 7. The model in this instance is one of the " Bombardier Beetles," and discharges, when seized or irritated, a jet of formic acid vapour quite powerful enough to scorch the skin of the finger severely and to leave an indelible brown stain on paper or cloth. The insect is quite conspicuous, being black with orange spots on the dorsal surface of the thorax and tegmina; the legs and antennae are entirely orange. The Locustid is somewhat larger, |