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 A HISTORY OF SUSSEX ' Eurynome [Leach] ? spinosa [Hailstone] ? aspera in a young state. Female.'^ But his experience was evidently at the time not such as to justify him in suggesting a new species, so that the alternative he offers of regarding his spinosa as the young of aspera has been accepted with general acquiescence. The readiness of all the spider-crabs to array themselves in borrowed plumes, and the nice adaptation of their own limbs and armature to the ingenious devices not of vanity but of self- concealment, are now well understood in principle. They still offer tempting opportunities for more detailed explanation or corroborative evidence on the part of patient and skilful observers. Outside of the genuine Brachyura is a section known as the primi- tive or anomalous Brachyura, sometimes called the Dromiacea. In it the oviducts of the female open not on the sternal plastron but on the first joint in the legs of the third pair. One species of this section, known as Dromia vulgaris, Milne-Edwards, though possibly only an occasional visitant, has a fairly good claim to be included in the fauna of the county. Bell says: 'In the Zoologist, 1848, p. 2325, occurs a notice of no fewer than nine full-sized specimens having been dredged on the coast of Sussex. Mr. Newman gives the details of its occurrence, and a figure of the species, having received it from Mr. George Ingall. About the same time my lamented friend Mr. Dixon, of Worthing, sent me three specimens which had been procured off Selsey Bill.' ^ Adam White, who gives the same reference to the Zoologist, speaks of the species as 'found at Beachy Head, Sussex, by G. Ingall, Esq., 1848.'^ White calls it the sponge-crab, obviously in allusion to the fact that this hairy ball of a crustacean often becomes covered with sponge. Of the legs not only the first pair are chelipeds, but also the fourth and fifth pairs, which are small and turned back over the carapace, have a minutely chelate ending. The species seems very closely related to D. rumphii, Fabricius, which ranges from the Red Sea to Japan, In the family Dromiida^, to which these species belong, there are two little lateral plates between the sixth and seventh segments of the pleon, a feature not very easy to observe in these hirsute animals, and one that when observed might by many be passed over as unimportant. It is how- ever of considerable significance, for while the true Brachyura have no appendages to the sixth pleon segment, in the Macrura these appendages attain a high development. We may note then that the two little plates in Dromia, on the supposition that they are vestigial appendages, supply a link between these two great contrasted groups of the decapod crustaceans. The anomalous Macrura are represented in Sussex by seven well known species, belonging to three families, the crab-like Porcellanids, the lobster-like Galatheids, and the Pagurida", known as hermit-crabs, though they are far from crab-like in nature or appearance. Parcel lana longicornis (Linn.), the ' minute porcelain crab,' is reported in the 1 Loudon's Magazine Nat. Hist. viii. 549. ^ British Stalk-eyed Crustacea, p. 371. ^ List of British Animals in British Museum, p. 23. 254