1558 THE VOYAGE OF H.M.S. CHALLENGER. 



9. July 1875, North Pacific, between Japan and Honolulu ; lat. 35° N.; surface. 

 (Brachyscelus crusculum, see p. 1547.) 



10. August or September 1875, Pacific Ocean; surface. (Brachyscelus acuticaudatus, 

 see p. 1555.) 



11. October 1875, South Pacific; surface. Two specimens (one Brachyscelus latipes, 

 see p. 1550, and one Brachyscelus bovallii, see p. 1553). 



To complete the account of the distribution so far as at present known, it may be 

 d ded that Thamyris antipodes, Spence Bate, was taken in lat. 58° S., long. 172° W.; 

 Thamyris rapax, Claus, at the Cape ; Thamyris globiceps, Claus, at Zanzibar ; 

 Thamyris mediterranea, Claus, near Naples; Thamyris elegans, Bovallius, in the Atlantic, 

 and Dana's Dairilia inseauipes, at the Philippine Islands. 



Genus Thamneus, Bovallius, 1887. 



1852. Daira(?) (pars), Dana, U.S. Explor. Expect, vol. xiii. pt. ii. pp. 981, 992. 

 1852. Dairilia (pars), Dana, U.S. Explor. Exped., vol. xiii. pt. ii. pp. 1519, 1596, 1G04. 

 1862. Dairinia (pars), Spence Bate, Brit. Mus. Catal. Amph. Crust., p. 309. 

 1885. ,, (pars), Bovallius, Some forgotten Genera of Aniphipoda, p. 9. 

 1887. Thamneus, Bovallius, Systematical List of Amph. Hyper., Bihang till K. Svensk. Vetensk - 

 Akad. Handl., Bd. 11, No. 16, p. 31. 



For the definition of this genus, see Note on Bovallius, 1887 (p. 591). The first 

 described species of the genus appears to be Dana's Dairilia (or Dairinia) depressa, but 

 Dana's generic name may well be allowed to drop, as well for the doubtfulness of the 

 spelling, as for the reason that Dana himself intended to identify it with Milne- 

 Edwards' Daira, from which it differs, and included in it three species, of which two have 

 already been assigned to other genera, and the third remains still doubtful. The name 

 Thamneus itself comes rather awkwardly near to the earlier Thamnus. 



Thamneus platyrrhynchus, n. sp. (PI. CXCVTIL). 



A very broad species, and also deep at the middle of the perseon ; the head broader 

 than long and considerably broader than deep ; the front of the head, though broad from 

 side to side, is very thin vertically, the rostral point not projecting but folded in on the 

 under side between the antennas ; the perseon has its segments a little dimpled on either 

 side ; the fourth and fifth segments are the broadest ; the first three segments of the 

 pleon, which are scarcely half as broad as these, have their postero-lateral angles slightly 

 rounded. The skin is covered with minute honeycomb markings. The outer margin of 

 the liver-tubes is deeply corrugated as in Simorhynchotus. 1 



1 See Claus, Die Platysceliden, p. 65, Taf. xvii. fig. IS. 



