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Show 1877.] CRUSTACEA, CHIEFLY FROM SOUTH AMERICA. 669 segment), in the much smaller antero-lateral lobes of the head-from P. granarus and P. liliputanus, Gay, from Chili, in the nearly equal joints of the flagellum of the external antennse-, &c. In a single specimen from Peru, the terminal segment is transverse-triangular, nearly of the form of that of P. poeyi, De Saussure, from Cuba ; but as this exactly agrees with the other specimens of the same series in other particulars, I do not regard this as more than an individual peculiarity. PORCELLIO FLAVO-VITTATA, sp. n. (Plate LXVIII. fig. 4.) More oblong in form, and a little more convex than the preceding species, with the granulations upon the body more distinctly marked, the sides of the body straighter. Colour blackish brown, variegated as in the preceding species. Lateral margins of the segments of the body with a marginal yellow band. Length 4 lines, breadth nearly 2 lines. Hab. Cayenne. This species is very nearly allied to the preceding; yet the differences above mentioned appear generally constant. In one specimen only, without antennse and uropoda, and which might, if in better condition, have proved distinct, is the lateral marginal yellow band entirely absent. All the specimens are unfortunately much mutilated. b. Convex, with the antero-lateral lobes of the head prominent. PORCELLIO AZTECUS. Porcellio aztecus, De Saussure, Mem. Soc. Phys. et Hist. Nat. Geneve, xiv. (part 2) p. 479, pl. v. fig. 38 (1858). Porcellio mexicanus, D e Saussure, I. c. p. 479, pl. v. figs. 39, 40 (1858). Hab. Peru (Lima). In the good series of specimens of this species in the collection, I have observed between younger and fully-matured animals just the differences that are instanced by D e Saussure as existing between P. aztecus and P. mexicanus, which I a m therefore inclined to consider different ages of one and the same species, well characterized by its large size, convex, finely and uniformly granulated body, the prominent antero-lateral lobes of the head, the form of the terminal segment, uropoda, etc. Porcellio interruptus, Heller (Reise der Novara, Crust, p. 136, 1865) from Chili, which, on account of the prominent antero-lateral lobes of the head, probably belongs to this section, differs in having the four anterior segments of the body much narrower than the preceding. P H I L O U G R I A , Kinahan1. To this genus I refer a species obtained in Peru and Guiana, and always occurring in the collection in the same tubes with Porcellio 1 According to Messrs. Spence Bate and Westwood=Itea, Koch, a name employed by Linnaeus for a genus of plants. I regret that I have not myself had PROC. ZOOL. Soc-1877, No. XLIV. 44 |