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 CRUSTACEANS Bouvier in 1896 says: 'As for Bell's Pagurus fasciatus, it is almost certainly a distinct species, hitherto peculiar to the British Isles, but it is too little known for its generic position to be fixed. It is notable for its oval chelae, of which the right is smaller than the left, for the very short wrist of its anterior feet, for its unarmed appendages, and above all for the transverse bands, alternately blue and red, which adorn the latter. It might well be a Caldnus.' J The Galatheidea embrace the crab-like Porcellanidae and the lobster-like Galatheidae. In the former family Cocks reports Porcellana platycheles (Pennant), from ' Bar, Gwyllyn-vase, Swanpool, etc. ; very common. Var. : equally common,' and P. longicornis (Linn.), from the same localities, also very common. Bell and Bate agree in thinking that the minute P. acanthocheles which Couch describes 2 is a young P. longicornis. Leach calls Galathea strigosa (Linn.) the Plaited lobster, Couch calls it the Plated lobster, and records it as common. Of G. squamifera, Leach, he says, ' Common, under stones at low-water mark.' 3 Cocks reports both from ' Bar, Gwyllyn-vase, Swanpool,' the former as not uncommon, the latter as very common. He adds G. nexa, Embleton, and a variety of the same, both from ' Gwyllyn-vase, trawl refuse ; not uncommon.' He also reports ' Munida Rondeletii, Bell. Adults from trawl refuse : young specimens under stones, low-water mark, spring tide ; not uncommon. One in my cabinet measures 7 inches and | of an inch in length.' This last species is the Astacus bamffius of Pennant, more properly called Munida rugosa (Fabricius). Bell gives the length as 3 in., and Cocks probably by a loose way of reckoning includes the long chelipeds in his measurement. Bell 'received it from Falmouth through the kindness of Mr. Cocks.' Earlier it had been found in Plymouth Sound by Mr. Prideaux, and later Bate says, ' I have taken this species, which is rare on the stony ground, in from 20 to 30 fathoms off the Dudman.' * Of G. syuamifera, which he calls G. squamosa, Bate says that it ' is not so frequent as G. strigosa and frequents deeper water.' Of G. nexa he says ' We have taken this specimen [? species] off the Cornish coast in 40 fathoms of water ' ; of G. dispersa, Bate, ' This is a smaller species than the two preceding, and is among our commonest form [forms] beyond low water ' ; of G. Andrewsii, Kinahan, ' This species was first found off the coast of Cornwall, but described by Prof. Kinahan from a female taken in Dublin Bay. It has since been described by Mr. Spence Bate from a male taken off the Cornish coast, the male differing from the female in having a much longer pair of chelate limbs. This species is tolerably frequent on the zoophytic ground from 10 to 50 fathoms, and the female is apparently much more abundant than the male. It is perhaps the smallest species of our local forms.' Lastly, under the heading ' Galathea digidistans, Spence Bate,' he quotes from the Report on the marine fauna and flora of the South Coast of Devon and Cornwall* his own account of a supposed new species G. digitidistans, in which the fingers of the chelae leave a gap or considerable distance between their inner margins even when closed. 6 At the time he suggested that it might be only an extreme form of the male of G. squamifera, and that suggestion is generally accepted as correct. G. Andrewsii is now recognized as identical with G. intermedia (Lilljeborg). It thus appears that in Cornwall there are five species of Galathea and one of Munida. A key for discriminating all these was supplied by Monsieur Jules Bonnier in 1888,' and has since been made available for English readers. 8 In Bell's often quoted work will be found an interesting account by R. Q. Couch, describing the habits of G. strigosa and its youngest stage. But for the metamorphoses of Galathea 9 and of many other Macrura the student should consult the successive essays of G. O. Sars, the illustrations to which will prove fruitful in instruction even to those who cannot read the Dano-Norwegian text. The genuine Macrura are not very sharply separated from the anomalous group. But they have no twisting of the pleon nor crab-like flexure of it. To these waters they supply several species of rather exceptional interest. They are divided among several tribes, the first of which, the Thalassinidea, is here represented by two families, the Callianassidae and the Axiidae. Callia- nassa subterranea (Montagu) is mentioned by Couch, though he does not specify whether or where he himself had found it. But Cocks gives it from ' stomach of the Trigla lyra, Trigla hirundo, etc. : not uncommon. Helford, Pendower Beach, etc. : occasionally.' Upogebia stellata (Montagu) and Upogebia deltaura (Leach) are both recorded by Couch, who says : ' I find what appears to me to be the latter species in abundance in Ray fish (Raia maculata and R. clavata) caught in from 30 to 50 fathoms of water.' 10 Cocks found the former ' in the stomach of Gadus aeglefinus, Trigla lyra : common, living specimens not uncommon at Helford,' and the latter ' in the stomach of the Gadus aeglefinus, etc. : common ; living specimens not uncommon at Helford and Pendower Sands.' The question seems to be still open whether we have to do with two species or only one. The 1 La Feuille des Jeunes NaturaRstes, No. 308, p. 9. ' Fauna, p. 76. 3 Ibid. pp. 76, 77. < < Revision,' p. 28. 5 Rep. Brit. Assoc. for 1867. 'Revision,' pp. 28, 29. 7 Bulletin scientifiyue de la Trance et de la Betgique (1888), pp. 41, 78. 8 Hist, of Crustacea, (Internal, sci. ser.) vol. Ixxiv (1893), pp. 175, 176. 9 Archiv far Mathem. und Naturv. (1889). 10 Fauna, p. 78. 267