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Show 526 REV. T. R. R. STEBBING O N CRUSTACEANS [May 22, second joint of the exopod traversed by a muscle evidently adapted for moving the terminal fascicle of long setae, about six in number. From the chelipeds specific distinctions can scarcely be derived, since in well-developed males of H. planatus there appear to be greater differences than any which can be pointed out between the chelipeds of that species and those of H. ovatus. Nicolet's Liriopea lucasii from Chile is founded almost exclusively on the robust character of the chelipeds, " ending in a hand almost globose, much inflated and of dingy blackish colour," the movable finger having a strong dentiform tubercle near the proximal end of the inner margin. These, however, are characters which may be rather indicative of age than species. The four following pairs of trunk-legs (or peraeopods) are naturally stouter in H. planatus, that being much the larger species ; but in the flattened terminal joint or finger there is also some difference of shape and armature, this joint in //. planatus being broader in comparison with its length, less curved, with the teeth of the inner margin not reverted, and implanted some on one side and some on the other of the border, whereas in H. ovatus they are in single file and provide the joint with a slightly backward directed serrature. In both species the two teeth nearest the acute nail are the largest, and the spaces between the spines have finely serrate setae, of which there is a group at the base of the margin. The broad, rounded pleon of the female and the terminally narrowed pleon of the male exhibit no characters for distinguishing the two species. Breadth of H.planatus about 9 mm., length a little less ; breadth of H. ovatus scarcely 7 mm., length a little less than the breadth. Mr. Vallentin reports H.planatus as " common under stones and kelp, Stanley Harbour." OxYRRHYNCHA. Fam. INACHLD2E. 1886. Inachidce,Miers,' Challenger' Brachyura, Reports, vol. xvii. pp. x, 2. Dana in 1852 (U.S. Expl. Exp., Crust, p. 77) in the Maiinea distinguished a family Eurypodidae, as having eyes retractile to the sides of the carapace, but without concealment below it. To this he referred three genera, Eurypodius, Oregonia, and Amathia. Miers in 1886 refers the family to Stimpson, who adopted it in 1870 with an acceptation regarded by Miers as equivalent to his own subfamily Inachinae (see J. Linn. Soc. Lond., vol. xv. p. 644, and ' Challenger' Report, p. 11). Alcock in 1895 divides the subfamily Inachinae into two alliances, Leptopodioida and Inachoida, to the latter of which Eurypodius is assigned with a score of other genera (J. Asiat. Soc. Bengal, vol. lxiv. pt. 2, p. 164). If the genus Leptopodia has to relinquish its name, as Miss Eathbun argues that it ought to do, the alliance Leptopodioida would naturally, in conformity with her view, be called Macropodioida. |