X 



1900.] FROM THE FALKLAND ISLANDS. 549 



Jcera and lais closely correspond; though the autepenultiraate 

 joint of the maxillipeds is rather less strongly developed in lais 

 than in Jcera, and, on the other hand, the inner plate of the first 

 maxillae is broader in lais. 



Iais pubescens (Dana). (Plate XXXVIII.) 



1853. Jcera puhescens, Dana, U.S. Expl. Exp. vol. xiii., Crust, 

 p. 744, pi. 49. figs. 9 a-d. 



1876. Jctra jnibescens, S. I. Smith, Bull. U.S. Nat. Mus., Contr. 

 Nat. Hist. Kerguelen, p. 63. 



1882. J(xra novce zealandice, Chilton, Tr. New Zealand Inst, 

 vol. XV. p. 189. 



1886. Iais hargeri, Bovallius, Notes on Fam. Asellidae, p. 50. 



1886. Iais pubescens, Bovallius, ibidem, p. 51. 



1886. Icera novce-zelanclice, Bovallius, ibidem, p. 49. 



1886. Jce7'a neo-zelanica, Thomson & Chilton, Tr. New Zealand 

 Inst. vol. xviii. p. 157. 



1886. Jcei-a pubescens, Beddard, ' Challenger ' Isopoda, Reports, 

 vol. xvii. p. 19, pi. 2. figs. 6-13. 



1887. Iais (Janthe) pubescens, Pfeff"er, Krebse von Siid-Georgien, 

 p. 19. 



1887. Jcera antarctica, Pfeffer, ibidem, pp. 19 & 94, pi. 7. 

 figs. 1-4. 



1888. Iais neo-zealanica, Chilton & Thomson, Tr. New Zealand 

 Inst. vol. xxi. p. 265 (Iais pubescens evidently intended). 



1891. Iais pubescens, Chilton, Trans. New Zealand Inst, 

 vol. xxiv. p. 26Q. 



1893. Jais pubescens, Thomson, P. E. Soc. Tasmania for 1892, 

 p. 15 (Jais misprint for lais). 



The association of this minute species with Sphceroma lanceolatum 

 (or gigas) is recorded by Dana tor Tierra del Fuego, by Professor 

 Smith and Mr. Beddard for Kerguelen Island. That they are 

 all three applying the name to the same species is, therefore, 

 highly probable. But Smith gives no description ; and Beddard's 

 description is accompanied by figures which do not in all respects 

 agree with our specimens from the Falkland Islands, the segments 

 of the body showing little or no lateral interval, and the head 

 having its front and sides cui-iously serrate. From the text, 

 however, it must be inferred, as Dr. Chilton has already pointed 

 out, that at least the second of these differences is due only 

 to an error on the part of the draughtsman ; the first apparently 

 depends on a very advanced stage of the brood-pouch in the 

 female. That the rami of the uropods are in the figure distally 

 clubbed instead of tapering, may well be due either to a casual 

 variation or a slight inaccuracy in the drawing. Iais har-geri 

 Bovallius, from the Strait of Magellan, differs in nothing from 

 the Falkland Island specimens, imless in size (" 3-4 mm.") and 

 in one or two comparative measurements of parts, which can 

 scarcely be trust woi-thy, since they vary with the bending or 

 straightening and other accidental conditions of the specimen 



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