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Beetles

March 7/70/ Bates. There are sexual differences in colour in some Longicorns: but extremely remarkable in several Prionidæ - they are larger & splendidly coloured Beetles, & the sexes of some differ wonderfully in colour; so that they were only thought quite distinct species.

In most of them the males of Pyrodes are duller & darker; the ♀ being more or less splendid golden-green. But in one Pyrodes the male is golden-green & ♀ with much rich red & purple.  (This most wonderful case of sexual differences is described by Bates under Pyrodes pulcherrimus in Transact. Ent. Soc. 1869 p. 50) In an Esmeralda both sexes very beautiful shining green. But ♂ has a red Thorax. In some of the Prionidæ male wonderfully smaller than ♀; with 3? pair of antennae very much larger & antenna simple in other species

Pyrodes, nigricollis was caught in copula with sexes very different.

(over

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on to which in majority of specimens the ♀s more splendid than ♂s. - Hence these can throw but little light on causes of beauty - Other structural & size difference in ♂, show that there has been a struggle between the males.