HISTORY OF THE FISHES OF MASSACHUSETTS. 259 



quantities of mackerel entangled in the nets, by biting them in pieces ; they also become 

 themselves entangled in the nets, and by their teeth and rough skin nearly destroy 

 them. 



Northerly, beyond the coast of Labrador, Dekay. Massachusetts, Stores. Connecti- 

 cut, Ayres. New York, Dekay. 



GENUS VI. SCYMNUS. Cuv. 



All the fins small ; two dorsal fins, the first but little before, and the second but little 

 behind the line of the ventrals ; no anal fin. Skin rough. Temporal orifices or spiracles 

 large, placed rather high upon the head, above as well as behind the eyes. Teeth in 

 the lower jaw crooked at the point, equilateral at the base ; in the upper jaw lancet- 

 shaped, but little curved ; the points in both jaws diverging from the centre. Gill open- 

 ings small. 



Scymnus brevipinna, Dekay. 



The Nurse or Sleeper. 



(Plate XXXVIII. Fig. 2. a. Teeth of upper jaw. b. Teeth of lower jaw. c. Spine in skin.) 



Somniosus brevipinna, Nurse or Sleeper, Lesueuk, Journ. Acad. Nat. Sciences, I. p. 222, pi. 



" " " " Storer, Report, p. 189. 



Scymnus brevipinna, Nurse, Dekay, Report, p. 361. pi. 61. fig. 202. 



" " " Storer, Synopsis, p. 



Leiodon echinatum, Wood, Proceed. Bost. Soc. Nat. Hist., n, p. 174. 



Color. A purplish gray, with numerous white spots distributed over' its surface. 



Description. Body robust, subtriangular to the posterior line of the first dorsal fin, 

 slightly convex in front of the dorsal fin, posterior to which it is cylindrical, and rapidly 

 diminishes in its diameter. The entire length of the specimen before us is seven feet 

 nine inches, measured from the tip of the snout to the extremity of the upper lobe of 

 the tail. The depth of the body, across from the first dorsal fin, is eighteen inches ; the 

 depth at the anal, is five inches ; the depth at the origin of the tail is three inches. The 

 length of the head is fourteen inches ; it is elongated, and terminates in a blunted snout, 

 which is rounded above, somewhat flattened beneath, and six inches deep at its base. 

 The eyes are circular, one and a half inches in diameter, situated seven inches posterior 

 to the tip of the snout. The nostrils are large, situated beneath the base of the edge of 

 the snout, four inches anterior to the eyes. 



The mouth is of moderate size ; the upper jaw is covered with five rows of small, 



