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Show 1902.] SPIDERS FROM BORNEO AND SINGAPORE. 233 ii. Mimic. Condylodera tricondyloides (Westw.). Plate X IX . figs. 2, 4, & 6. Models. Cicindelidce. Plate XIX. figs. 1, 3, & 5. I was fortunate enough to discover in Sarawak the remarkable Locustid, Condylodera tricondyloides, originally described in 1837 by Westwood from Java (Trans. Linn. Soc. vol. xviii. p. 409); the type specimen was at first placed by Westwood in his collection of Oicindelidse, " regarding it as an immature Colliurus or Tricondyla" (I.e. p. 419). Another Javan specimen was actually given the MS. name of Tricondyla rufipes by Duponchel, so close is the resemblance of this highly deceptive Locustid to a Tiger-beetle. Both these historical specimens are now in the Hope Collection at Oxford, and have been compared with the Sarawak specimens by Mr. Malcolm Burr. My first specimen, which is somewhat larger than the type, was found in jungle in the neighbourhood of Kuching, running about on the ground amongst dead leaves and other vegetable debris, an environment much frequented by a large Tiger-beetle, Tricondyla cyanea (Dej.) var. wallacei (Thoms.), with which this Locustid is almost identical in appearance (compare Plate XIX. figs. 1 & 2). The shape, size, coloration, and even the gait of the mimic so closely resembled the corresponding traits of its model, that I did not suspect the importance of my find till a careful examination of the collecting-box had been made some hours after the time of capture. The colour of the head, thorax, and abdomen of the Condylodera is a dark shining blue, the femora of all the legs are red, the hind femora (which are only slightly swollen) having in addition a proximal black band. The head with its large prominent eyes, somewhat flattened face, and conspicuous jaws, is very Cicindelid in appearance. The antenme are of extreme tenuity and are about 2g to 3 times as long as the body. The densely-punctured prothorax is globosely swollen about its middle, the swelling being marked off from the elevated anterior border and posterior portion by broad constrictions. The tegminal and wing rudiments lie very closely adpressed to the body and do not disturb the even contour of the dorsal aspect. The abdomen, though hardly so bottle-shaped as are the elytra and abdomen of the model, is not widely different in appearance, and the intersegmental membranes are quite concealed except on the ventral surface, where the scuta are small, as is usual in this group of insects. The model is so common and so well known a species that it is unnecessary to describe its general appearance; the above brief description of its mimic will suffice to show in how many superficial points the two insects agree, and superficiality of resemblance is the key-note of mimicry. Another specimen of this mimetic Locustid of the same size was obtained a few months later in the same locality; and both these |