84
THE BIOLOGY O F EUPHAUSIIDS
1952; Wiborg, 1955; Brunel, 1959; Nemoto, 1959, 1962a; Brinton,
1962a ; Grainger, 1962 ; Prefontaine and Brunel, 1962 ; Drobysheva,
1963, 1964; Holmquist, 1963; Ponomareva, 1963 ; Dunbar, 1964.)
Genus Nematoscelis G. 0. Sars, 1883b : 27; 1885 : 126-127
Nematoscelis dificilis Hansen, 191 1
N . diflcilis Hansen, 1911: 48-50, fig. 18; Esterly, 1914a: 12, pl. i, figs. 1, 3,
4, 12, 15, pl. ii, figs. 22,34,35 ; Banner, 1950 : 29-31 ; Boden et al., 1955 : 364-366,
fig. 40 ; McLaughlin, 1965 : 41-44, figs. 1-3.
N . dificilis and N . megalops are very closely related species. N .
dificilis is confined to the North Pacific between about 35"N and 45"N
in the North Pacific Drift but extends southwards to about 20"N in the
California Current (Fig. 28). Banner records it a t 51"N off British
Columbia. Sheard found it off southeastern Australia but this requires
confirmation. Seems to live between 150 m and the surface. Length
22-25 mm. (Sheard, 1953; Brinton, 1962a; Ponomareva, 1963.)
Nematoscelis megalops G. 0. Sars, 1883
N . megalops G. 0. Sars, 1883b : 27-28 ; 1885 : 127-131, pl. xxiii, figs. 5-10,
N . megalops occurs in the South Pacific, throughout the Atlantic,
and in the Indian Oceans (Fig. 28). Atlantic : Zelikman (1964) records it
a t 68' 45" 38'50'E but it more frequently occurs between 65"N, from
Greenland to Norway, southwards in the west to about 30"N, in the
east to the equator ; it is present in the Mediterranean and recorded from
the Sea of Marmara and the eastern Mediterranean. It has not been
found between the equator and about 20"s off Africa nor from the whole
of the South American coast. It is present in the southeastern Atlantic
between 20"s and 50"s. Pacific : restricted to the South Pacific between
33"s and 48" to 54"s but the main populations are located along 40'5.
Indian: found in the Straits of Mozambique and in the central ocean
along about 40"s ; there is a single record of Illig's a t 2' 30" 76'74'E
and so there may be a northern band of distribution in the Indian
Ocean. Probably occurs below 300 m during the day, migrating towards
the surface a t night. Length 20-26 mm. (Sars, 1885; Ortmann, 1893;
Hansen, 1905a, 1908a, 1915; Tattersall, 1908b, 1911, 1925, 1927;
Stephensen, 1913; Jorgensen, 1918; Colosi, 1922b; Denis, 1929; Illig,
1930; Frost, 1935; Leavitt, 1935,1938; Ruud, 1936; Fish and Johnson,
1937 ; Bigelow and Sears, 1939 ; Legendre, 1940 ; Einarsson, 1945 ;
Marshall, 1948 ; Whiteley, 1948 ; Moore, 1950, 1952 ; Boden, 1954,
1961a; Lewis, 1954; 0stvedt, 1955; Bary, 1956; Nepgen, 1957;
pl. xxiv; Denis, 1929 : 72-73.
THE BIOLOGY O F EUPHAUSIIDS
1952; Wiborg, 1955; Brunel, 1959; Nemoto, 1959, 1962a; Brinton,
1962a ; Grainger, 1962 ; Prefontaine and Brunel, 1962 ; Drobysheva,
1963, 1964; Holmquist, 1963; Ponomareva, 1963 ; Dunbar, 1964.)
Genus Nematoscelis G. 0. Sars, 1883b : 27; 1885 : 126-127
Nematoscelis dificilis Hansen, 191 1
N . diflcilis Hansen, 1911: 48-50, fig. 18; Esterly, 1914a: 12, pl. i, figs. 1, 3,
4, 12, 15, pl. ii, figs. 22,34,35 ; Banner, 1950 : 29-31 ; Boden et al., 1955 : 364-366,
fig. 40 ; McLaughlin, 1965 : 41-44, figs. 1-3.
N . dificilis and N . megalops are very closely related species. N .
dificilis is confined to the North Pacific between about 35"N and 45"N
in the North Pacific Drift but extends southwards to about 20"N in the
California Current (Fig. 28). Banner records it a t 51"N off British
Columbia. Sheard found it off southeastern Australia but this requires
confirmation. Seems to live between 150 m and the surface. Length
22-25 mm. (Sheard, 1953; Brinton, 1962a; Ponomareva, 1963.)
Nematoscelis megalops G. 0. Sars, 1883
N . megalops G. 0. Sars, 1883b : 27-28 ; 1885 : 127-131, pl. xxiii, figs. 5-10,
N . megalops occurs in the South Pacific, throughout the Atlantic,
and in the Indian Oceans (Fig. 28). Atlantic : Zelikman (1964) records it
a t 68' 45" 38'50'E but it more frequently occurs between 65"N, from
Greenland to Norway, southwards in the west to about 30"N, in the
east to the equator ; it is present in the Mediterranean and recorded from
the Sea of Marmara and the eastern Mediterranean. It has not been
found between the equator and about 20"s off Africa nor from the whole
of the South American coast. It is present in the southeastern Atlantic
between 20"s and 50"s. Pacific : restricted to the South Pacific between
33"s and 48" to 54"s but the main populations are located along 40'5.
Indian: found in the Straits of Mozambique and in the central ocean
along about 40"s ; there is a single record of Illig's a t 2' 30" 76'74'E
and so there may be a northern band of distribution in the Indian
Ocean. Probably occurs below 300 m during the day, migrating towards
the surface a t night. Length 20-26 mm. (Sars, 1885; Ortmann, 1893;
Hansen, 1905a, 1908a, 1915; Tattersall, 1908b, 1911, 1925, 1927;
Stephensen, 1913; Jorgensen, 1918; Colosi, 1922b; Denis, 1929; Illig,
1930; Frost, 1935; Leavitt, 1935,1938; Ruud, 1936; Fish and Johnson,
1937 ; Bigelow and Sears, 1939 ; Legendre, 1940 ; Einarsson, 1945 ;
Marshall, 1948 ; Whiteley, 1948 ; Moore, 1950, 1952 ; Boden, 1954,
1961a; Lewis, 1954; 0stvedt, 1955; Bary, 1956; Nepgen, 1957;
pl. xxiv; Denis, 1929 : 72-73.