5 1 8 Memoir Sears Foundation for Marine Research 



Trunk at origin of -pectoral: breadth 13.7; height 13.4. 

 Snout length in front of: outer nostrils 2. i ■■, mouth 8.3. 

 Eye: horizontal diameter 1.3. 

 Mouth: breadth 11.7; height 3.5. 

 Nostrils: distance between inner ends 6.3. 

 Labial furrow length from corner of mouth: upper 1.3. 

 Gill opening lengths: ist 2.2; 2nd 2.8; 3rd 2.8; 4th 2.8; fth 3.1. 

 First dorsal fin: vertical height 3.5; length of base 6.6. 

 Second dorsal fin: vertical height 2.5; length of base 4.9. 

 Caudal fin: upper margin 19.3; lower anterior margin 13.8. 

 Pectoral fin: outer margin 12. i; inner margin 6.S'-, distal margin 6.2. 

 Distance from snout to: ist dorsal 40. 7; 2nd dorsal 66.6; upper caudal 80.7; pec- 

 toral 23.7; pelvics 63.2. 



Interspace between: ist and 2nd dorsals 19.5; 2nd dorsal and caudal 8.5. 

 Distance from, origin to origin of: pectoral and pelvics 39.5; pelvics and caudal 

 18.9. 



Trunk subcylindrical anteriorly, but tapering posteriorly, its greatest height about 

 % of its length to origin of caudal, somewhat compressed, about % as thick as high oppo- 

 site the pectorals and 70 to 80% as thick as high at caudal peduncle, but so soft and flabby 

 that one lying on the dock bears little resemblance to its form when in the water." Back 

 smooth between dorsals, but with a faintly indicated dermal ridge along midline ex- 

 tending rearward from opposite pectorals about to origin of ist dorsal." Caudal pe- 

 duncle described as with an indistinct lateral longitudinal ridge, much as in Squalus, but 

 this is not visible in the mounted specimens we have examined. Dermal denticles conical, 

 curved rearward, longitudinally fluted, with high axial and lower lateral crests, their 

 bases quadrilateral, moderately closely spaced and of essentially the same form over the 

 trunk as a whole. 



Snout thick, fleshy, broadly rounded in front, somewhat contracted between nostrils 

 and eyes, its length in front of mouth about Vs of length of head. Eye approximately 

 circular and very small, its diameter only about V5 to % of length of snout, its center about 

 opposite front of mouth. Spiracle a little above level of eye and behind latter by a distance 

 about 1V2 times the diameter of eye. Gill openings low on sides of neck, about evenly 

 spaced, very small and all about twice as long as diameter of eye, the 5th, slightly the 

 longest, close in front of origin of pectoral. Nostril nearly transverse and much closer to tip 

 of snout than to mouth, its anterior margin only slightly expanded. Mouth transverse, 

 very little arched, its breadth about equal to length of snout in front of mouth. Labial 

 furrows extending rearward for a considerable distance from corner of mouth and part 

 way along upper and lower jaws:" 



11. For this reason many of the earlier representations of it are no better than caricatures, for they picture it as 

 enormously stout of body, which is not the case. 



12. The exact extent cannot be stated for the Atlantic specimens studied because of their condition. 



13. On the specimens examined, the lower labial furrow has been entirely obliterated in the process of mounting, 

 the upper and posterior folds mostly so as well. 



