296
V. R. NAIR and T. S. S. RAo:
and the position of the patches is comparable in both periods. The average number of
specimens per standard haul is the same in both seasons (Table 2). This suggests that on
average the abundance of the species in the surface layer is not directly affected by the
monsoons.
2.Krohnitta subtilis (GRASSI, 1881)
(Figs. 2a and 2b)
This species is occasionally represented in the samples, the range of abundance being
0- 3.1 % of the total chaetognaths in the samples. K. subtilis has higher representation
in the western Arabian Sea, particularly near Somalia (400 per std. sample), but is very
scarce in the collections taken off the coasts of India and in the SE part. The SW monsoon
30°
JOo
N
20°
10·
0 '
5
10°
60°
70°
E 80"30.
N
200
70°
Fl!5' 2 a. Geographical distribution of K. subtilis during the SW monsoon
JOO 30°
N
20°
10°
0°
S
10'
60°
~ , ::t. . ' 1-<. !
500
60"
10°
E 80" 300
N
70°
Fig. 2 b. Geographical distribution of K. subtilis during the NE monsoon