THE BIOLOGY OF WOOD-RORINQ TEREDINID MO1,LUSCS
435
terms of dry weight of the body in Nausitom hedleyi. This is probably
the highest value recorded for any mollusc. Whet'her this apparently
higher value is associated with thc peculiar esbuarinc habitat and the
restricted nature of its breeding or with any other physiological
peculiarity is, however, not evident.
9:. I
1 mq
24 -
20 -
16I 2 -
N
D
J
F
rd
A
M
J
J
A
s o
Fra. 43. Curves illustrating the average dry weight of the specimens in respcctive
months (A) together with the monthly variations in the percenhgc of glycogen, (€3)
and protein, (C) content of the body of Nnusitora hedleyi.
Correlation between glycogen values and the breeding period is
evident in the present study. Such seasonal changes and high values
for glycogen during the non-breeding resting phase have also been
noticed in oysters (Okasaki and Kobayashi, 1928 ; Tully, 1934 ; Durve
and Bal, 1961). Greenfield (1953) was unable to notice any seasonal
change in the nitrogen and glycogen content or any apparent difference
in the concentration of these components between gravid and nongravid individuals of the same size. It may also be seen from the
A.P.B.-9
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