348 



Fishery Bulletin 90(2). 1992 



Figure 8B 



Size-frequency histograms for male 

 (M) and female (F) Cynoglossus lida 

 (July-December) caught commer- 

 cially off Porto Novo, India, October 

 1981-September 1982. 



Probability plot method Cumulative percentage 

 distribution of lengths was calculated for C. arel and 

 C. lida, and plotted against the midpoints of length- 

 groups on probability paper (Fig. 91, J). These points 

 formed approximately straight lines, but slight devia- 

 tions could be recognized. Based on the probability 

 plots, male C. arel attained 194 mm, 272 mm, and 

 333 mm in the 1st, 2d, and 3d years, respectively, while 

 females reached 201, 312, and 393 mm for these years. 



In C. lida, males attained 151, 188, and 218mm, while 

 females reached 153, 188, and 216 mm, in the 1st, 2d, 

 and 3d years, respectively. 



von Bertalanffy's equation Plots of Lfi- 1 against 

 Lt , showing a straight-line relationship for C arel and 

 C. lida, were drawn. A least-square line was then fitted 

 and an estimate of L^ was obtained (Fig. 9A,C, E,G). 

 By this Ford-Walford graph, L^ was 570 mm for male 



