[fraser] COPEPODS PARASITIC ON FISH 49 



Argulus pugettensis Dana 



Argiilus pugettensis Dana, U.S. Exploring Exped., 1838-1842, vol. 



XIII. The Crustacea. 1852, p. 1351. 

 Wilson, Proc. U.S. Nat. Mus., vol. XXV, 1903, 



p. 711. 

 Wilson, Proc. U.S. Nat. Mus., vol. XXXV, 



1909, p. 432. 

 Wilson, Contr. to Can. Biol., 1912, p. 87. 

 The rainbow trout, Salmo iridens, and the blue perch, Taeniotoca 

 lateralis, served as the hosts for this species in the specimens examined 

 by Wilson. They have also been found on the steelhead trout, Salmo 

 gairdneri, and the silver perch, Phanerodon furcatus. 



Family CALIGIDyE 

 Caligus gltrnardi Kroyer 



Caligus gurnardi Kroyer, Naturh. Tidsskrift, Ser. 3, vol. II, 1863, 



p. 150. 

 Wilson, Proc. U.S. Nat. Mus., vol. XXXV, 1909, 



p. 439. 

 Scott, T. and Scott, A., Br. Parasitic copepods, 



1913, p. 52. 



Many specimens have been found in different stages and on a 

 great variety of hosts, one in a plankton haul, May 9, 1917, made in 

 Northumberland channel, at the edge of the Dodds narrows tide- 

 rip. The hosts were: the steelhead, Salmo gairdneri, the dog salmon, 

 Oncorhynchus keta, the rock cod, Sebastodes sp., and the Pacific her- 

 ring, Clupea pallasii. The young stages were found on herring less 

 than two inches long, when the scales were just beginning to appear. 



Wilson has reported some from other points on the Pacific coast 

 from the spring salmon, Oncorhynchus tschawytscha, and the rat fish, 

 Hydrolagiis collei. 



' Lepeophtheirus bifidus new species 

 Pl. II, Figs. 22-35 



Female: Carapace nearly circular but flattened posteriorly; 

 frontal plates well defined; posterior sinuses broad, widely separated, 

 leaving a median lobe almost half the greatest width of the carapace; 

 lateral lobes broad and well rounded. Free thoracic segm.ent half the 

 width of the genital segment, of medium length. Genital segment 



