Fishes of the Western North Atlantic 545 



Extreme breadth at outer extremity of -pectorals: 54.O. 

 Trunk at origin of pectoral: height 8.0. 

 Snout length in front of: outer nostrils Oj mouth o. 

 Eye: horizontal diameter 1.55 distance between eyes 8.4. 

 Spiracles: distance between 8.1 ; from spiracle opening to eye 2.7. 

 Mouth: breadth 11.8} height 3.2. 

 Nostrils: distance between inner ends 4.8. 



Gill opening lengths: ist7.l} 2nd 6.7; 3rd 6.6; 4th 6.2; 5th 6.0. 

 First dorsal fin : vertical height 4.9 ; length of base 4. i . 

 Second dorsal Jin: vertical height 4.5 ; length of base 4.0. 

 Caudal fin: upper margin 12.O; lower margin 14.3. 

 Pectoral fin: outer margin 26.5; inner margin 13.8; distal margin 14.0. 

 Distance from snout to: ist dorsal 65.6; 2nd dorsal 76.O; upper caudal 88.0; pec- 

 toral 16.8; pelvics 37.8. 



Interspace between: ist and and dorsals 7.O; 2nd dorsal and caudal 8.5. 

 Distance from origin to origin of: pectoral and pelvics 20.9; pelvics and caudal 

 49.8. 



S. argentina resembles S. dumeril so closely in general proportions and in the shape 

 of the pectoral fin" that we have found no clear distinction between the two species in 

 most of their proportional dimensions, and the teeth are of the same number ( ^^^ ) and 

 shape. However, the distance from the spiracle to the eye is only a little more than V2 

 (55% ) as long as the diameter of the eye in argentina, but nearly as long as the eye (91%) 

 in dumeril. The inner nasal barbel of argentina is spatulate (tapering in dumeril), while 

 there is a broad quadrate lobe between the two barbels, with a second lobe-lilce expansion 

 just basal to the outer margin of the outer barbel on the outer side in argentina, which is 

 not the case in dumeril (cf. Fig. 103 D with 103 G). A further difference if minor is that 

 the dermal fold along the front of the head is not expanded at all opposite the corner of the 

 mouth in argentina, but is slightly expanded there in dumeril (although much less so than 

 in the European squatina; Fig. 103 C). 



S. argentina differs from armata of the west coast of South America in the contour 

 of the margin of the nostril (cf. Fig. 103 D with 103 H) ; it differs further from armata 

 in that the distal margin of its pectoral is marked off from the inner margin by a definite, 

 narrowly rounded corner, whereas in armata the one margin grades insensibly into the 

 other in an even curve. 



Color. Described as gray-brown above, marked with many small oval cinnamon- 

 colored spots; white below." 



Size. Said to grow to a length of 1.7 meters (5V2 feet). 



37. In the original illustration of argentina (Marini, Physis B. Aires, lo, 1930: 6) the outer corner of the pectoral 

 is shown as considerably more obtuse than a right angle. But it is only a little more than a right angle in the 

 specimen we have studied, and Ribeiro's (Arch. Mus. nac. Rio de J., r^, 1907 : pi. 10) photograph of a Brazilian 

 specimen shows about a right angle. 



j8. The only specimen we have seen has not only lost the color pattern, but is now stained red with iron rust. 



