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Show 1900.] FROM THE FALKLAND ISLANDS. 539 lucida of Sars the second maxillae "are distinguished more particularly by the short and broad form of the terminal joint," which is broader than long; whereas this appendage in the large and apparently careful figure given by Dana has the terminal joint considerably longer than broad. In Sars's figure the third peneopods have the last three joints together not shorter than the preceding joint; while in Dana's figure they are decidedly shorter, though not to so great an extent as in his description. Again, in Sars's pellucida the subapical processes of the telson are "finely denticulate along their inner edge," a character belonging also to E. spinifera Sars and E. latifrons Sars, but to none of the other species described in the 'Challenger' Eeport. A character of this minute kind might, it is true, easily have escaped observation by Dana, but it so happens that he expressly applies the epithet " naked " to these processes in E. pellucida. It follows therefore, I think, that for the E. pellucida of Sars some other name must be used, but this point will be considered to better advantage later on. The identification of E. splendens Sars with the species so named by Dana is also, as Sars admits, beset with difficulties. Thus, in Sars's form the carapace has a denticle about the middle of each lower margin ; but Dana says " carapace a little compressed, not toothed." As he does not show or speak of a toothed carapace in any of his four species, this particular negation remains rather mysterious. With another character it is different. Sars writes of E. splendens, " Antennular peduncle without any trace of dorsal lobes," having previously written in regard to the antennular peduncle of his E.pellucida, "it is more particularly distinguished by the basal joint having at the end above a conspicuous erect leaflet or membranous lobe." But Dana says of E. pellucida, "first basal joint of inner antenna not produced at apex," and of E. splendens, " first joint of inner antennae oblong and produced at apex"; so that either this character is of no importance, or Dana's two species do not agree with the forms to which Sars has attributed their names. Eather curiously, too, Dana says of E. pellucida, " basal scale of outer antennae a little longer than base," but of E. splendens, " basal scale of outer antennae shorter than base" (or, in the Latin, "basin non superans"); whereas Sars states it is the basal scale of E. sp>lendens that is decidedly longer than the base, that of his E. pellucida being scarcely at all longer, thus again inverting the relations as given by the two authors. According to Sars the inner plate of the uropods in splendens is a little shorter than the outer; in Dana's detail-figure it is fully as long. Sars says, "The length of the largest specimen reaches about 18 mm., and the species attains accordingly a somewhat larger size than Euphausia pellucida." Dana, on the other hand, who had some fifteen or twenty specimens at command, says: " Length about half an inch," half an inch being also the length which he gives for E. pellucida. The relative lengths of the joints in the thoracic legs appear to agree in the two forms; but later authors seem to have attached less specific importance to this character than Dana |