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PACIFIC SCIENCE, Vol. XVIII, July 1964 
and Harvey (1926), Chacko (1950), Doncaster 
(1903, as S. septata) , Fowler (1906), George 
(1949, 1952), John (1933, 1937), Oye (1918), 
Rao (1958 a, b), Rao and Ganapati (1958), 
Schilp (1941), Tokioka (1955, 1956*), Vara- 
darajan and Chacko (1943). 
S. pulchra was observed in the Indonesian 
seas and in the Equatorial Indian waters as far 
as the Mauritius Islands. Other records in the 
Indian Ocean: Baldasseroni (1915), Burfield 
and Harvey ( 1926) , Doncaster ( 1903 ) , Fowler 
(1906), George (1949, 1952), Oye (1918), 
Rao (1958^, *), Rao and Ganapati (1958), 
Ritter-Zahony ( 1910), Schilp (1941) and To- 
kioka (1955). 
S. minima , cosmopolitan in the warm and 
temperate waters, should be expected in the 
Central Indian Ocean waters. However, it was 
only observed in very small numbers at stations 
11, 13, 15 (11° 15' S— 103° 32' E, 17° 01' S— 
93° 28.6' E, 12° 57.9' S— 75° 13.6' E) respec- 
tively. The samples studied showed an abundance 
of S. bipunctata and a scarcity of S. minima, 
whereas the opposite was found by Tokioka 
(1956^). The samples examined by Tokioka 
(loc. cit.) were taken on December 11, 1954 — 
January 16, 1955, and the Monsoon samples 
from October 22, I960 — January 9, 1961, which 
is practically during the same monsoon regimen. 
Therefore, no speculation could be made based 
on the monsoon influence in the distribution of 
these species. In the samples from the Naga 
Expedition in the South China Sea and the Gulf 
of Siam ( Alvarino, unpublished data), 5 1 . bi- 
punctata appeared also more abundant than S. 
minima, unlike the quantitative pattern shown 
by both species in the North Pacific. Other rec- 
ords of S' minima in this ocean: Ritter-Zahony 
(1910, 1911), Schilp (1941), Thomson (1948), 
and Tokioka (1955, 195 6a). 
S. regularis extended in the Equatorial waters 
as far as the Mauritius Islands. Although no 
specimens of S. regularis were observed at the 
stations in the Indonesian seas, it is reasonable to 
assume that the species extends along those 
paths to the Pacific. Large numbers of S. regu- 
laris were observed in the samples of the Naga 
Expedition, from the Gulf of Thailand and the 
South China Sea (Alvarino, unpublished data). 
The lack of positive records in regions where 
the presence of this species is to be expected, 
is likely due to the small size of the S. regularis 
which could easily escape owing to the size of 
the mesh used in the nets. The species has been 
recorded by previous workers in the Indonesian 
region. Other records in the Indian Ocean: Bur- 
field and Harvey (1926), Doncaster (1903), 
Fowler (1906), George (1952), Menon (1945), 
Oye (1918), Rao (1958^, *), Rao and Ganapati 
(1958), Ritter-Zahony (1910, 1911), Schilp 
(1941), and Tokioka (1955, 1956a, b). 
S. decipiens extended along the strata below 
250 m from the northern part of the region 
covered in the Indian Ocean to 37° S. In the 
Pacific it extended along those strata from 40° 
S (Alvarino, 196Ab; Bieri, 1959). Other records 
in the Indian Ocean: Burfield and Harvey 
(1926), David (1958), Fowler (1906) as S. 
sibogae, Rao and Ganapati (1958), Ritter- 
Zahony (1911), and Schilp (1941). 
S. planctonis was observed along the northern 
part of the Subantarctic West Wind Drift ex- 
tending into the Subtropical Convergence in the 
Indian Ocean. It was found below the 200-m 
level up to 36° S, and in deeper waters up to 
22° S (mid- water trawl from 2000 m deep, one 
specimen). The connection of the populations 
of S. planctonis of the Indian and Pacific oceans 
evidently occurs along the south Australian seas. 
Its distribution in the Pacific was also found 
limited by the Subtropical Convergence towards 
the north (Alvarino, 19 64*). S. zetesios, a species 
closely related to S. planctonis, extends along 
the mesoplanktonic domain of the Tropical, 
Equatorial, and Central Indian waters. The two- 
dimensional pattern of distribution for 5'. zetesios 
overlaps that of S. planctonis at mid-water trawl 
station 8 (22° 04' S — 63° 02' E), where one 
specimen of S. planctonis and two of S. zetesios 
were observed in a haul taken from 2000 m. 
At mid-water trawl 9 (33° 19' S— 72° 34' E) 
taken from 1878 m, 38 specimen of S . zetesios 
were recorded with only three specimens of S. 
planctonis. The S. planctonis domain, then, ex- 
tended south of that boundary. 
The Burfield and Harvey (1926), George 
(1952), and John (1937) records of S. planc- 
tonis are most likely to be 5'. zetesios in view of 
the location of the observations and the drawings 
and descriptions of the species included in the 
