MULLIDAE OF THE WESTERN NORTH ATLANTIC 



415 



For length of ventral lobe of caudal fin (fig. 16) 

 the rates of increase to about 60 mm. and beyond 

 100 mm. are constant and similar. There is an 

 upward shift in the line depicting the ultimate 

 rate in the 70- to 100-mm. size range. For length 

 of dorsal lobe and caudal fin (fig. 17) tliere is an 

 inflection at 80 to 100 mm. with the initial rate of 

 increase slightly higher than the ultimate rate. 



Interorbital space (fig. 18) appears to experi- 

 ence similar and constant rates of increase below 

 about 40 mm. and above about 60 mm., with a 

 considerable lower rate of increase in the 40- to 

 60-nim. size range. An inflection occurs in data 



for length of barbel (fig. 19) between 45 and 55 

 mm., with the rate of increase constant and lower 

 beyond the inflection than initially. 



For snout length (fig. 20) the rate of increase 

 beyond an inflection at 40 to 50 mm. is constant 

 and higher than the initial rate. 



For length of the first lower-limb gill raker (fig. 

 21) there is apparently no increase between the 

 smallest size in which raker lengths was deter- 

 mined (about 21.6 mm.) and about 55 mm. Be- 

 yond 55 mm. this part increases in length at a 

 constant rate through the largest size examined. 



I 

 I- 



40 



70 100 



STANDARD LENGTH 



130 

 (MM.) 



190 



Figure 9.— Relation of head length to stjindiird length of Miillldae of the western Norlh Atliintic. For PxMidupeneuK 

 maoulatus. large black circle indicates smallest iiietainori>hose<l specimen (41.0 miii.t and large open circle indicates 

 large pelagic form ( .")9.5 nun. ) . 



