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Show 1900.] FROM THE FALKLAND ISLANDS, 529 his Eurypodius latreillii seems almost certain, because he does not begin according to custom with a Latin, followed by an English description of it, but with the explanation of the figures in the plate, appending as usual more or less desultory descriptive observations. Tbe explanation of the figures refers to plate 3. figs, la-c, without any mention of tig. d, which appears three years later in the explanation of the Plates of the Atlas as representing the " abdomen, enlarged two diameters." On Plate 3 of the Atlas there is indeed an abdomen or pleon, enlarged two diameters, and its last segment is subtriangular, or one might fairly say triangular ; but there is no letter or number on the plate to show that the figure belongs to Eurypodius latreillii, and it may, I think, be argued that Dana assigned it at a venture to his latreillii and then described the pleon of that species from it. According to Dana," the posterior margin of the inter-antennary cavity, next to the outer antenna?, is reflexed downward " in his septentrionalis and brevipes, but not so reflexed in his latreillii. Tozzetti does not take any notice of this distinction, in which Guerin's latreillii agrees with septentrionalis. In Eurypodius latreillii from the Falkland Islands there is on the underside of the rostrum behind the cusps a groove ending in a strong forward pointing hook, as described by Guerin and indicated in Tozzetti's figures, pi. 1. fig. 18 (latreillei) and pi. l.fig. 9 (audouini), as well as in Dana's pi. 2. fig. 7 a (brevipes), but not in his pi. 2. fig. 6 a (septentrionalis) nor yet in his pi. 3. fig. 1 a (latreillii). The opinion of Miers that all the forms assigned to Eurypodius prior to 1886 belong to a single variable species is highly probable. It is unfortunate that he should have overlooked the discussion by Tozzetti, on which his judgment would have been so valuable. Of two dried specimens brought home by Mr. Vallentin, the larger is 52 m m . long from tip of rostrum to end of the carapace, and 32-5 m m . broad at the widest part; the carapace, excluding the rostrum, is nearly 4-L times as long as the rostrum. Found clinging to the stems of Macrocystis. Mr. Vallentin says : "I have frequently detected one of these crustaceans slowly retiring to the root, as the stem of Macrocystis was being hauled into m y boat for examination, and if the rate of hauling was suddenly quickened, one might possibly secure the specimen by making a frantic grab at it before it slipped off. All the four pairs of ambulatory appendages modified to enable the animal to cling to this weed." Guerin fancied that they were modified for swimming. MACEUEA. ANOM ALA. Section Lithodinea. 1849. Lithodeacea, de Haan, Fauna Japonica, Crustacea, pp. viii, xxii, 197, 213, etc. 1850. Lithodina, Brandt, Bull, phys.-math. Acad. St.Petersbourg, vol. viii. p. 54. |