no. 2065. TEE CRUSTACEA EUPHAUSIACEA— HANSEN. 101 



33. THYSANOESSA GREGARIA G. O. Sars (1883). 



1885. Thysanoe'ssa gregaria G. 0. Sars, Challenger Rep., vol. 13, p. 120, pi. 21, 



figa. 8-17; pi. 22. 

 1905. Thysanoessa gregaria H. J. Hansen, Bull. Mus. Ocean. Monaco, No.. 42, 



pp. 27 and 28. 

 1911. Thysanoessa gregaria H. J. Hansen, Bull, l'lnet. Ocean. Monaco, No. 210, 



pp. 39 and 43, fig. 15. 

 1913. Thysanoessa gregaria H. J. Hansen, Hep. Crust. Schizopoda Swedish 



Antarctic Exp., p. 37, pi. 6, figs, la-lb. 



Occurrence. — Material is at hand from four stations in the north- 

 west Atlantic and from four places in the north Pacific: 



A. Atlantic stations.— -Sta. 2091. September 21, 1883. Lat. 40° 

 Or 50" N\; long. 70° 59' W. 4 specimens. 



Sta. 2095. August 5, 1883. Lat. 39° 44' N.; long. 70° 03' W. 

 2 specimens. 



Sta. 2104. November 5, 1883. Lat. 38° 48' N.; long. 72° 40' 30" 

 W. 4 specimens. 



Sta. 2098. October 1, 1883. Lat. 37° 40' 30" N.; long. 70° 37' 

 30" W. 4 specimens. 



B. Localities in the Pacific. — Bering Island (about lat. 55° N.). 

 Leonhard Stejneger, 1882-83. 1 specimen (female). 



Sta. 4793. June 16, 1906. Lat, 54° 48' N.; long. 164° 54' E. 

 Toperkoo Island, not far from Bering Island. 300-0 fathoms. 1 

 specimen (female). 



May 1, 1884. Lat. 39° 25' N.; long. 150° 28' W. Lieut. G. M. 

 Stoney, U. S. N. 1 specimen (adult male). 



Sta. 4397. April 1, 1904. Lat. 33° 10' 15" N.; long. 121° 42' 15" 

 W. 5 specimens (male). 



Remarks. — As already stated by me in 1913/ this species varies 

 considerably in several features, to which may be added that even 

 the eyes seem to be somewhat variable in size. I have attempted, 

 without success, to find differences in the shape of the processes of 

 the copulatory organs of specimens from the North Pacific and the 

 subantarctic ocean south of the Atlantic. The male taken by 

 Lieutenant Stoney is 12 mm. long and has the eyes large. 



Distribution.— This species is known from the temperate north 

 Atlantic, the temperate south Atlantic, and southward in the sub- 

 antarctic ocean to lat. 53° 34' S.; furthermore, from the south 

 Pacific and the temperate and boreal north Pacific, but it has never 

 been taken in the tropical area and, so far as I can see, perhaps not in 

 the subtropical belts of any ocean. Further details on this topic may 

 be found in the papers quoted above. 



1 Rep. Crust. Schizopoda Swedish Antarctic Exp. 



