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Show 1902.] SPIDERS FROM BORNEO AND SINGAPORE. 251 which will devour a single specimen of beetle or butterfly entirely for the sake of curiosity, only manifesting disgust or the reverse when that curiosity is fully satisfied. Of the mimicking species it is not necessary to say much, their resemblances to their models being in every case most obvious. Amongst the Lamiidse, the Phytceciince again yield the majority of mimetic species (a newly-discovered Dciphisici, yellow in colour, is banded with black in almost identically the same manner as C. annularis) (compare figs. 34 & 31 on Plate X X .) ; and amongst the Cerambycidae, the Lepturince are also fruitful in this respect. One species of Leptura, with reddish head and prothorax and yellow black-banded elytra, is closely similar to Demonax mustela (compare figs. 40 & 39, Plate X X .) : another species allied to Leptura histrionica (Pasc.), black with cream-coloured bands, is not readily distinguishable from Xylotrechus decoratas (compare figs. 42 & 41) and one or two species of Demonax. Plate XX. and its explanation should be consulted for the representation of other examples given in Table III. but not further indicated in the text. Polyphida clytoides (Pasc.), Psalanta chalybeata (Pasc.), and Chlorisanis viridis (Pasc.) I have never seen, but good figures of them are published in Pascoe's paper on the Longicornia Mala.yana (Trans. Ent. Soc. ser. 3, vol. iii.). The remaining mimics of the iridescent green Callichroynince, viz. Nos. (4), (10), and (12) in Table III., are shown in figs. 47, 48, and 44 on Plate X X . and their models in figs. 45, 46, and 43. [The mimetic resemblance to the Clytince exhibited by so namy species of distantly related Bornean Longicorns is of extreme interest. The widespread species of this dominant group have developed, in a great majority of cases, a black and yellow or black and orange transverse banding, which superficially resembles the characteristic appearance of wasps and hornets. This rough resemblance is further heightened by the active movements of the living beetle, which suggest those of a Hymenopterous rather than a Coleopterous insect. Such an appearance is found in Clytince of many species from the whole Palsearctic and Nearctic belt, from Mexico, Malaya, Australia, and probably many other countries. An Australian species, Aridceus thoracicus (Donovan), has the deep brownish-orange colour of the alternate stripes, as well as the comparatively few broad black bands which are characteristic of wasps from the same region. Clytanthus sex-guttcctus (Lucas) from Morocco suggests the appearance of a Mutillid or perhaps a Clerid with a Mutillid form of colouring. The JBornean Sclethrus amuenus (Gory) mimics the aggressive Coleopterous Tricondyla (Cicindelidse), while species of the Tillo-morphince, allied to the Clytince, mimic ants, e. g., Euderces picipes (Fab.) of N. America and Clytellus westwoodi (Pasc.) of Borneo. Thus we witness within the limits of one large group of Coleoptera a great development of mimicry of aggressive specially protected forms. Such mimicry has been hitherto assumed to be Batesian (pseudaposematic), although the dominance |