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Show 224 ON THE BEETLES OF THE GENUS CALLIGRAPHA. [Feb. 4, 17. BARBUS, sp. A very young specimen, 5 cm. long, from Lake Rudolf, cannot be specifically determined. 18. MORMYRUS ZAMBANENJE, Ptl'S. In a specimen from Geledi on the Webi Shebeli (19.1.95) the dorsal fin is a little more than half as long as the anal. D. 21. A. 41. 3. Remarks on the System of Coloration and Punctuation the Beetles of the Genus Calligrapha. By MARTIN JACOBY, F.E.S. [Eeceived January 2, 1896.] The paper which I have the honour to lay before the Society gives a short account of a somewhat exceptional feature in the Coleoptera, which occurs amongst the Chrysomelidae in the genus Calligrapha, but in no other families of Coleoptera to my knowledge. This genus has its metropohs in Central America, and is represented by numerous prettily marked species, ah more or less closely allied. In these insects, the ground-colour of the elytra is always pale yellow, but often assumes a golden hue when the insect is alive: this yellow ground-colour is marked with metallic brown or blue, sometimes violet spots, and stripes, but in many species this colour (if it can be so called)is replaced by reddish-fulvous or brown, not of a metallic hue. The elytra of most Coleoptera are impressed with more or less deep punctures, either arranged in longitudinal rows or irregularly distributed, and even when the elytra are pubescent the punctures will be seen when the hairs are removed. In no other insects of this order do the punctures seem to be dependent on the coloration or pattern of the elytra, or vice versa, but both go their own way ; but in the case of the genus Calligrapha the interesting observation may be made that nearly all stripes or spots, no matter how few or many or what may be their shape, are bounded or surrounded at their margins by a row of deep punctures, deeper than those of the ground-colour, beyond which the colour does not extend. This is very remarkable, since I know of no instance in which punctures assume a circle in other species, much less that circular and longitudinal rows of punctures are found in the same individual according to the design as is the case in Calligrapha. The question which strikes one now is, how could this coloration influence a deep punctuation or the latter the colouring of the insect: a few instances are found in which some of the spots or bands are free from punctures at tbeir lower portion, but then- outlines are just as well defined as those which have the punctures complete. According to Burmeister, the punctures of the elytra are formed by the interruption of the chitinous matter, causing small pits or punctures to be formed, but the regularity |