Fishes of the Western North Atlantic 



409 



Exposed nostrils: distance between inner ends, males (>.() to 7.3, females 6.2 to d.d. 



Gill openings: lengths, ist, males 1.8 to 2.2, females 1.8 to 1.9; 3rd, males 1.9 to 

 2.2, females 1.8 to 1.9; 5th, males i.o to 1.2, females 0.9 to 1.2; 

 distance between inner ends, ist, males 15.0 to 15.9, females 15.9 to 

 16.6; 5th, males 10.4 to 11.4, females 11.3 to 11.6. 



Pelvics: outer margin, males 8.4 to 9.1, females 7.6 to 9.4. 



Figure 97. Gymnura micrura. A Male, 420 mm wide, from Beaufort, North Carolina (U. S. Nat. Mus., 

 No. 51940). B Nostrils, nasal curtain, and mouth of same, about i X. C Side view of tail of same to show color 

 pattern and upper and lower tail folds, about i X. i) Cross section of tail at about midpoint, about 2.8 X. 

 E Sector from outer-anterior margin of disc to show detail of color pattern, about I X. /" Juvenile female, about 

 216 mm wide, from Apalachicola, Florida (U. S. Nat. Mus., No. 127298) to show shape of front of disc. 



Distance: from tip of snout to center of cloaca, males 53.0 to 57.8, females 50.0 

 to 51.5; from center of cloaca to tip of tail, males 23.0 to 24.7, females 

 21.9 to 23.2. 



Remarks. There is a considerable sexual difference in certain proportions, notably 

 in the length of the disc, in the length of the snout in front of the orbits as well as in 

 front of the mouth and in the distance from snout to center of cloaca. 



Disc lozenge-shaped, about 1.6 to 1.7 times as broad as long in males, 1.7 to 



