300 COLLECTIONS FROM MELANESIA. 



is somewhat elongated, trigonous, and has a small spinule at its 

 distal end : the rami arc subequal and longer than the base, yet not 

 greatly elongated as in some species. The colour (in spirit) is yel- 

 lowish, usually closely and somewhat irregularly punctulated with 

 black. Length of the largest example about 8 lines (17 millim.) ; 

 breadth nearly 3.4 lines (7 millim.). 



These specimens very nearly resemble examples referred to L.gau- 

 dichaudii from Madjica-Sima in the Museum collection ; but the 

 body is less distinctly granulated, and the granulations do not gene- 

 rally extend over the median dorsal line of the postabdominal seg- 

 ments, and the notches of the terminal segment are not distinctly 

 toothed. In one specimen, however, I have observed a continuous 

 line of granules bordering the posterior margins of the postabdominal 

 segments. 



In the uncertainty that exists regarding the true nomenclature of 

 not a few species of this genus, I prefer to retain the name of aus- 

 traliensis as a designation for this variety. Mr. Thomson* has de- 

 scribed a species from Dunedin, New Zealand (L. quadrata), which is 

 evidently nearly allied to the L. australiensis, but may, perhaps, be 

 distinguished by the less prominent postero-lateral angles of the last 

 I ostabdominal segment, which is described as " subquadrate, with 

 the angles hardly projecting." 



2. Ceratothoa imbricata. 



Oniscus imbricatus, Fabr. Mantissa Insect, i. p. 241 (1787). 



Cvniothoa imbricata, Fabr. Ent. Syst. ii. p. 503 (1793) ; Suppl. p. 301 

 (1798). 



Cymothoa banksii, Leach, Diet. Set. Nat. xii. p. 353 (1818) ; Bes- 

 marest, Consul. Crust, p. 309 (1825) ; M.-Edwards, Hist. Nat. 

 Crust, iii. p. 273 (1840) ; Heller, Eeise tier Novara, Crust, p. 148 

 (1865). 



Cymothoa trigonocephala, M.-Edwards (nee Leach ?), Ann. Set. Nit. 

 ser. 2, iii. pi. xiv. tigs. 1, 2 (1835) ; Crust, in Guv. Rec/ne Animal, 

 pi. lxv. fig. 2 ; Hist. Nat. Crust, iii. p. 272 (1840), var. ; GuSrin, 

 Icon. Crust. Eigne Animal, pi. xxix. tig. 2 (after Milne-Edwards ). 



Ceratothoa trigonocephala, Heller, Novara Crust, p. 148 (1865) ; 

 Thomson, Trans. New-Zeal. lust. xi. p. 233 (1879), var.; Hasivell, 

 Cat. Austr. Crust, p. 282 (1882), after M.-Edwards. 



? Cvmothoa approximans, White, t. c. p. 110 (1847). 

 Ceratothoa banksii, Miers, Cat. New-Zeal. Crust, p. 135 (1876). 



A small specimen, presenting no distinctive external sexual cha- 

 racters, is in the collection from Port Jackson, 0-5 fins. It is un- 

 doubtedly identical with a somewhat larger specimen from the same 

 locality in the British-Museum collection, taken 4 ' from the mouth of a 

 bream." The type example of C. banksii (thus designated in the hand- 

 writing of Dr. Leach) is of larger size, and is said to have been obtained 

 in the Xew-Zealand seas ; it presents no distinctions which can be 

 regarded as of specific importance, and the description which I have 



* Trans. New-Zeal. Inst. xi. p. 232 (1879). 





