806 



Fishery Bulletin 97(4), 1999 



proportionally, followed by the head mass. Thus, S. 

 pharaonis weight gain and loss were accounted for 

 mainly by the mantle and head mass that underwent 

 fluctuation in mean dry weight index during the 

 study. 



The MI and HI diminished considerably as gonad 

 development proceeded. The largest decrease in Ml 

 and HI of females occurred in spring and summer 

 (from March to September), as shown in Figure 3. 

 These indices decreased from 52% to 41% and from 

 34% to 28%, respectively. In contrast, during the 

 same period the gonads (GSI, NGI ) exhibited devel- 

 opment; GSI increased from 1% to 9% and NGI in- 

 creased from 2% to 7%. VI increased rapidly from 

 May to November, from 5% to lO'/f . DGI showed little 

 change over the whole sampling period (ranging be- 

 tween 7% and 10% ). 



By contrast, in male Sepia pharaonis, the MI, HI, 

 and DGI remained relatively constant throughout the 

 entire sampling period (Fig. 4). The pattern of VI 

 was consistent with the situation in female, increas- 

 ing from 5% to 8% during the period from May to 

 October There was a gradual increase in GSI and 

 SCI from November, reaching the highest value in 

 May (=1.3%), and spawning after June was indicated 

 by a decline in GSI and SCI. 



Percentage of protein, water content, and maturity 

 stage 



The mean percentage composition of protein and 

 mean percentage of water content in the mantle and 

 head of females for maturity stages II-IV is shown 



