THE COPENHAGEN MUSEUM AND OTHER SOUECES. 429 



The species included are : — 1. Echinogammarus Berilloni (Catta), 1875, in certain 

 fresh waters of Western Europe ; 2. K cevrucosus (Gerstfeldt), 1858 ; 3. E. Maackli 

 (Gerstfeldt), 1858 ; 4. E. ocJiotensis (Brandt), 1851, from Ochotsk Bay; and the 

 following tw^enty-three, all instituted under the generic name Gammarus by Dybowsky 

 in 1874, and all, like the second and third, found in Lake Baikal : — saphirinus, Czerskii, 

 lividus, viridis, cyaneus, testaceus, Sophice, fuscus, murinus, aheneus, sarmatus, capreoltis, 

 TJzzolzewii, stenophtJialmm, schamanensis, leptocerus, toxophthahnus, vittatns, Fetersii, 

 violaceus, ibex, ParvexU, poI[farthn(s. Here, too, may perhaps be placed the obscure 

 Gammarus mut'Uus of Abildgaard, 1789. 



Heterogammarus, n. g. 



In general like Gammarus, without dorsal teeth or carinse or noticeable processes of 

 head- or side-plates ; accessory flagellum of first antennae more than one-jointed ; oviter 

 ramus of third uropods two-jointed ; )mt separated from Gammarus by one or more of the 

 following characters : — the peduncle of first antennae longer than that of the second ; the 

 hand of the first gnathopods larger than that of the second; the first uropods very 

 short. 



The generic name alludes to the character of the genus as a second self to Gammarus. 



The species included are the following eight, from Lake Baikal, instituted by 

 Dybowsky in 1874, imder the generic name Gammarus : — Stanlslavii, Sophiaiiosii, 

 capellus, ignotus, Flori, bifasciatus, branchialis, and albulus ; the last being given by 

 Dybowsky as a var. albula of Gammarus Florl. 



Parapallasea, n. g. 



Median carina not represented on peraeon or first to third segments of pleon. Fourth 

 side-plates broader and not less deep than the preceding, emarginate behind. Flagellum 

 of first antennae longer than the peduncle ; accessory flagellum elongate. Third to fifth 

 peraeopods Avith second joint expanded. Telsou deeply cleft. Other characters agreeing 

 with Palhuea. 



Tlie species included are : — 1. Parapallasea Eo7'otoski i {Dyhowsky), 1874; 2. P. La- 

 gowsk'u (Dybowsky), 1874; 3. P. PuzijlUi (Dybowsky), 1874; all from Lake Baikal. 



Carinogammaeus, n. g. 



Distinguished from Gammarus by having carinate segments, the carina medio-dorsal 

 only ; relative proportions of the peduncles in the two pairs of anteuntie, of the two pairs 

 of gnathopods, and of the inner and outer ramus of the third uropods, variable. 



The species included are: — 1. Carinogammarus cimiamomeus (Dybowsky), 1874 ; 

 2. C. IVagll (Dybowsky), 1874; 3. C. pulchellus (Dybowsky), 1874; 4. C. Seidlitzii 

 (Dybowsky), 1874 ; 5. C. rhodophthalmus (Dybowsky), 1874— all these five from Lake 



