352 NEW-YORK FAUNA. 
GENUS LAMNA. Cuvier. 
Snout pyramidal, with the nostrils under the base. Branchial apertures all in front of the 
pectorals. ‘Temporal orifices wanting. 
Oss. Some of the recent English systematic writers have added to these characters, the 
following: ‘First dorsal in advance of the pectorals, and sides of the tail carinated.” We 
prefer the less restricted characters assigned to this genus by Cuvier. 
THE MACKEREL PORBEAGLE. 
LaMNA PUNCTATA, 
PLATE LXII. FIGS. 206 & 207. —(CABINET OF THE LYCEUM.) 
The Green-backed Shark, Squalus punctatus. Mitcuiut, Trans. Lit. and Phil. Soc. Vol. 1, p. 483. (Young.) 
Lamna punctata, Mackerel Shark. Storer, Massachusetts Report, p. 185, pl. 3, fig. 2. 
Characteristics. Teeth in front long and sinuous; behind, triangular, and all with smooth 
edges. Anal small, and posterior to the second dorsal. ‘Tail with a 
keel on its sides; lobes not greatly unequal. Length four to eight feet. 
Description. Body cylindrical, fusiform. Head small, with a blunt pyramidal snout six 
inches long, measured from the nostrils. The surface, under the lens, exhibits numerous 
minute plates, each with three parallel longitudinal elevated lines, producing a roughness when 
the hand is moved towards the head. A carina on each side of the tail, about two feet in 
extent, highest in the middle ; a deep indentation on the upper and lower sides of the tail, in 
the shape of a horseshoe. On the surface of the head are four series of punctures on each 
side, commencing nearly opposite to the posterior margins of the orbits, dilating and extend- 
ing to within about an inch of the extremity of the snout. Immediately before the eyes is a 
large patch of similar punctures, which extend slightly beyond the nostrils ; on the under side 
of the snout is a triangular patch of similar punctures, extending to within 0°7 of the extre- 
mity ; a regularly curved series of punctures from the end of the carina, concurrent with the 
back, and ending just anterior to the origin of the first dorsal fin. All these punctures are 
the apertures of mucous ducts, which are filled with a transparent jelly. ‘The skin, at the 
posterior base of the dorsal and pectoral fins, was eroded by some parasitical animal. (Dr. 
Storer noticed the Anthosoma smithit on his specimen.) Eyes moderate, lateral 2°3 in dia- 
meter, and eight inches distant from each other. Nostrils doubly curved, sublateral. 'The 
posterior branchial aperture farthest from its antecedent. 
Teeth, of various shapes and sizes, disposed in from three to five rows. In the lower jaw, 
the front teeth, (see figure 206, 4) are largest, 0°9 long measured to the space between the 
roots, irregularly lanceolate, the external and sometimes the internal edge rounded and waved ; 
the margins with a finely elevated crest, which is smooth, obsoletely serrate under the lens ; 
flattened in front, and rounded, approaching a triangular form behind ; occasionally they are 
