646 ON CRUSTACEA BROUGHT BY DR WILLEY FROM T^E SOUTH SEAS. 



LiGiA viTiENSis, Dana. 



1853. Lygia vitiensis, Dana, U. S. Expl. Exp., Crust., p. 741, pi. 49, fig. 5 a, h. 

 1885. Ligia vitiensis, Budde-Lund, Isopoda terrestria, p. 271. 



Dana's single specimen from 'the Feejees' was 'mutilated in its last abdominal 

 segment, besides wanting the stylets and antennae.' In all Dr Willey's specimens the 

 stylets are unfortunately missing. The eyes are large, widening outward, the space 

 between them more than half the horizontal length of the eye, not less than half as 

 in Dana's Ligia hawaiensis. The second antennae in natural position reach back to the 

 beginning of the pleon ; the last joint of the peduncle is considerably longer than the 

 penultimate ; the flagellum is rather longer than the peduncle, with 28 to 30 joints. 

 In the last two pairs of trunk legs, that is, the fourth and fifth peraeopods, there is 

 a tuft of hairs on the hind margin at the base of the double unguis. The terminal 

 segment of the pleon has the postero-lateral angles rather long, acute, but otherwise 

 its apical border is very unlike that described and figured by Dollfus for Ligia 

 exotica, Roux, the extremity being as Dana says ' very low, triangular' and the inter- 

 mediate angles being, as his figure shows, quite blunted down. This margin and the 

 sides of the segment carry minute spinules, of which two flank the little apical 

 emargination or notch. Dana speaks of the surface of the body as quite smooth, 

 but there are scattered hairs in our specimens. Colour, the usual diversified iron 

 grey. 



Length, from front of head to end of telson, 13 — 17'5 mm., only a single 

 specimen attaining the latter dimensions. For Ligia exotica Budde-Lund gives 20 — 30 

 ( — 35) mm. for the length. 



Habitat. Matadona, China Straits, British New Guinea. ' From face of cliff, with 

 fresh water species, far above tide-mark.' 



Fam. Oniscidae. 



1885. Onisci (Section II.), Budde-Lund, Isopoda terrestria, p. 75. 



1893. Oniscidae, Stebbing, History of Crustacea, p. 426. 



1898. Oniscidae, Sars, Crustacea of Norway, vol. 2, p. 169. 



1900. Oniscidae, H. Richardson, The American Naturalist, vol. 34, p. 302. 



Budde-Liind's family Onisci comprises two sections, the Armadilloidea and Onis- 

 coidea, corresponding to the two families Armadillidiidae and Oniscidae. In the 

 latter group he includes a gen-us Oniscus, which he divides into five subgenera, 

 Oniscus, Philoscia, Alloniscus, Lyprohius, Scyphax. It is by most writers, I believe, 

 thought more convenient to regard all these as independent genera. Budde-Lund 

 himself assigns twenty-three species to Philoscia, and several have been added since 

 his book was published. 



Gen. Philoscia, Latreille. 



1804. Philoscie (probably misprint for Philoscia), Latreille, Hist. Nat. Crust, et 

 Insectes, vol. 7, p. 43. 



