Fishes of Massachusetts. 537 
inches across; distance from this to the middle of 
the tail, nine inches. 
At the base of the fleshy portion of the Caudal fin, 
a deep groove on each side, running half the length 
of this portion. Caudal fin unequal in its lobes ; the 
upper, measuring along its curve, twenty-three 
inches; the lower, eighteen. Depth of the caudal 
fin at its extremities, two and a half feet. 
Near the anus, imbedded in the flesh, I found a 
specimen of the “ Anthosoma Smithii" of Leach. 
Large specimens of this shark, which is usually 
found only three or four feet long, have been mis- 
taken for the “Carcharias glaucus," Blue Shark, 
by our fishermen. Although the Blue Shark may 
exist in our waters, still as I have not been able to 
meet with it, nor with any one who has seen it, upon 
whose scientific accuracy I can implicitly rely, I 
have erased it from our catalogue, and substituted 
this species. The remarks made in my former 
report are applicable here, and are, therefore, intro- 
duced. 
Spinax. Cuv. 
Generic characters. Two dorsal fins, with a 
strong spine at the anterior edge of each; no anal 
fin; temporal orifices garn j ^ teeth d 1n several rows, 
small ees cutting. 
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VOL. two. nv. =r 260 š 
