50 70 90 110 130 150 170 



PRIBILOF IS 

 N=1438 



110 130 150 170 



LU 



en 



CL~ 



100 

 90 

 80 

 70 

 60 



— 50 



LU 



£ l 

 LU 

 0- 30 



20 



10 







50 70 90 110 130 150 170 



CARAPACE LENGTH (MM) 



g>@g » — gHIXD 



PRINCE 

 WILLIAM SD. 



N=151 



50 70 90 110 130 150 



CARAPACE LENGTH (MM) 



170 



FIGURE 2.— Percent of blue king crab females that were mature, within 3 mm size intervals, as a function of size. Dotted lines indicate the car- 

 apace lengths corresponding to the 50% maturity levels on the fitted logistic functions (solid lines). Sample sizes (N) are indicated. 



which describes a pair of intersecting straight lines 

 and has the intersection point as a parameter. One 

 such model, which has been previously used (Somer- 

 ton 1980b) to describe the relation between premolt 

 and postmolt carapace size, is 



Y=A+BX 



Y= Y* + C(X-X*) 



x<x* 

 x>x* 



where Y and X are the logarithms of chela height and 



carapace length, X* is the intersection point on the X 

 axis, and Y* is the intersection point on the Y axis, 

 (Y* = A + BX*). The model has four parameters. A, 

 B, C, and X*. 



This model was fit to morphometric data using an 

 iterative computer technique (FORTRAN program 

 MATURE 2 is available from the senior author). 

 First, a lower and an upper bound of an interval on 

 the X axis are chosen such that the intersection point 

 is contained within the interval. Second, X* is set 



623 



