162 
ZOOLOGY. 
to the batteries of the eel are supplied by the ventral 
branches of about two hundred pairs of spinal nerves. 
Succeeding these fish are the herrings, represented by 
the common English herring, Clupea harengus, which in- 
habits both sides of the North Atlantic, extending on the 
American side from the polar 
regions to Cape Cod; the alewife, 
P oniolobus pseudoliarejigus, 
wliich ranges from Newfound- 
land fo Florida; the shad, Alosa 
sapidissirna, which has the same 
geographical distribution as the 
aicwife; and the menhaden or 
pogy, Brevoortia tyrannies, 
which extends from the coast of 
Maine to Cape Hatteras. These, 
with the cod, hake, haddock, 
salmon, and a few other species, 
comprise our most valuable ma- 
rine food-fishes. The fisheries 
of the United States yield about 
$44,000,000 annually, whilst 
those of Great Britain amount in 
value to about $40,000,000, and 
those of Norway to about $10,- 
000,000. 
The herring (Fig. 206) is a 
deep-water fish which visits the 
Fig. 205.-^.predo, a siiuroid fish, coast in Spring in immense 
S^L^he"^^ sc^^'^^ls/ ^^l^icl^ f^^^al^s are 
three times as numerous as the 
males, to spawn, selecting slioal water from three to four 
fathoms deep in bays, where the eggs hatch. At this 
season, and early in the summer, hundreds of millions are 
caught, especially on the Canadian, Newfoundland, and 
Labrador coasts. The English whitebait is the young of 
the herring. The herring is caught in deep nets with 
