COHEN and RUSSO: VARIATION IN FOURBEARD ROCKLING 



Table 5. — Frequency distributions of numbers of pectoral fin 

 rays in Enchelyopus cimbrius from eight geographical areas. 



FIGURE 3— Enchelyopus cimbrius. A. USNM 213501, head 

 length 62.8 mm, off Cape Cod, note absence of dark pigment 

 along base of fin with short rays. B, USNM 217843. head length 

 33.2 mm, Gulf of Mexico, note dark pigment along base of fin 

 with short ravs. 



Table 4, — Frequency distributions of numbers of vertebrae in 

 Enchelyopus ctmbnus from eight geographical areas. 



Table 6. — Frequency distributions of total numbers of gill rak- 

 ers on first arch in Enchelyopus ctrnhrtus from eight geographi- 

 cal areas. 



tic 53 (50.5-297); Iceland 10 (151-327); Europe 27 

 (93.8-300). 



Analysis of covariance was used to compare re- 

 gression lines (Tables 7, 8) for six measurements 

 that we have treated as linear based on a 

 coefficient of determination ir^) of 0.73 or higher 

 (Table 8). Two measurements, ventral fin length 

 and barbel length, had coefficients of determina- 

 tion ranging from 0.42 to 0.61 and were not further 

 analyzed. 



Fishes from all si.x geographical areas demon- 

 strated overall coincidence at the 0.05 level of sig- 

 nificance in two characters, head length and upper 

 jaw length. Hypotheses concerning overall coinci- 

 dence of regressions for the other characters were 

 rejected and hypotheses concerning the equality of 

 slopes and intercepts were simultaneously tested. 



The hypothesis concerning the equality of slopes 

 was rejected for the Dj-Dj distance versus stan- 

 dard length regression lines. Regression data were 



snout to first dorsal fin (pre D, distance); first dor- 

 sal fin to the dorsal fin beginning posterior to the 

 row of small filamentous rays (D,-D:i distance); 

 head length; pectoral fin length; upper jaw length; 

 horizontal diameter of eye (orbit length); length of 

 barbel on lower jaw; and ventral fin length. Num- 

 bers of specimens measured and their size ranges 

 (standard length in millimeters) were: Gulf of 

 Mexico 17 (125-228); Southern Atlantic 46 (125- 

 263); Intermediate 29 1 104-202); Northern Atlan- 



TABLE 7. — Significance of differences in six morphometric 

 characters in Enchelyopus cimhrius from six geographical re- 

 gions. Independent variable is standard length. 



'Rejection of hypothesis of equality at the 05 level of significance 

 'Reiection of hypothesis of equality at the 001 level of significance 



95 



