REPORT ON THE AMPHIPODA. 1399 



1869. Metoecus, Norman, Last Report on Dredging among the Shetland Isles, p. 287. 



1870. Metoecm, Boeck, Crust, amph. bor. et arct., p. 6 (86). 

 1872. Tauria, Boeck, De Skand. og Arkt. Amph., p. 88. 



1879. Hyperia (pars), Edward, Smiles' Life of a Scotch Naturalist, p. 435. 

 1882. Tauria, Sars, Oversigt af Norges Crustaceer, pp. 19, 75. 



1882. Hyperia (pars), Bovallius, On some forgotten Genera among Crust. Amph., Bihang till 

 K Svensk. Vetensk.Akad. Handl., Bd. 10, No. 14, p. 17. 



1885. ,, „ Carus, Prodromus Fauna? Mediterranean, p. 422. 



1886. „ „ Gerstaecker, Bronn's Klassen und Ordnungen, Bd. v. Abth. ii. p. 491. 

 18S7. Hyperoche, Bovallius, Systematical List of Amph. Hyper., Bihang till K. Svensk. Vetensk.- 

 Akad. Handl., Bd. 11, No. 16, p. 18. 



1887. ,, Bovallius, Arctic and Antarctic Hyperids, Vega-Exped., Bd. iv. p. 563. 

 1887. ,, Hansen, Malacostraca marina Groenlandise oecidentalis, p. 58. 



For the original definition of Metoecus, see Note on Kr0yer, 1838 (p. 179). The 

 name being preoccupied must yield to Hyperoche, for the definition of which see Note 

 on Bovallius, 1887 (p. 588). In his Arctic and Antarctic Hyperids Bovallius adds the 

 observation that : — 



" Hyperoche is easily distinguished from Hyperia, its nearest relative, by the form 

 of the carpal processes of the first two pairs of pereiopoda [First and Second Gnathopods] 

 being compressed, knife-shaped, sharply serrated. Also the carpi of the third and fourth 

 pan [First and Second Per&ojyods] are different in form, with serrated hinder edges, or 

 dilated as in the genera Parathemisto and Euthemisto. The general habitus is very 

 similar to that of Hyperia." Hansen considers that both " Hyperoche Kroeyeri," 

 Bovallius, and " Hyperoche Luetkeni," Bovallius, should be made synonyms of Hyperoche 

 medusarum (Kr0yer). Sars unites Boeck's Tauria abyssorum with Kr0yer's species, and 

 it is probable enough that Hyperoche prehensilis (Bate and Westwood) is only a young 

 male of that species ; its chief distinction, the dilated fifth joint in the perseopods, is 

 shown by Fritz Mulder to be a character of the young. Bovallius gives " Hyperoche 

 Martinezi" as the name of Fritz Midler's "Hyperia. Martinezii," and in view of the 

 wording of Bovallius' generic definition it may be noticed that in that species the fourth 

 joint or carpus of the first perseopod is figured by Midler 1 with serrated hinder edge and 

 ddated. These two characteristics are also combined in the first perseopods of the 

 Challenger species, though they are not very strikingly developed. In Hyperoche 

 medusarum (Kr0j^er) Hansen found the fourth joint prolonged downwards in a serrate 

 process only on the first pera3opods, and not also on the second. 



Hyperoche cryptodactylus, n. sp. (PL CLXX.). 



The Head short, not specially deep ; all the segments of the peraeon distinct, the pleon 

 deeper than the perseon, the posterodateral angles of the first three segments produced 

 in short sharp points. Liver-tubes very large ; heart large and with strong walls, 



1 Fur Darwin, tran?., p. 77. 



