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BULLETIN OF THE BUREAU OF FISHERIES 
differ among themselves in their choice of diet, 50 nor were any of the gadoids common 
to American and North European waters studied by Lebour. However, several 
North Sea members of the family were feeding on small copepods — mainly Pseudo- 
calanus — and Calanus was taken freely as the larval fishes grew in size. Dannevig, 
too, writes that numbers of newly-hatched cod placed under observation at the 
hatchery at Flodevigen, Norway, took no food until the yolk sac had been absorbed, 
and thereafter fed from the first on such animals as mollusk larvae, nauplii, etc., 
"seeming to despise the innumerable diatom forms which are likewise present in 
the water” (Dannevig, 1919, p. 48). Evidently this applies to the American cod 
as well, because young fish 12 to 20 millimeters long have been observed to feed 
exclusively on copepods at Woods Hole (Bumpus, 1898), and according to Mead 
(1898) copepods are likewise the favorite diet there for young sculpins and sand 
launce (Ammodytes). 
Judging from the general similarity between the planktonic communities of the 
two sides of the North Atlantic, there is every reason to assume that the dietary 
lists which Lebour gives for very young herring and mackerel would apply as well 
(in a general way) to the Gulf of Maine as to the North Sea. For the former species 
this diet consisted chiefly of larval gastropods, with copepods, particularly Pseudo- 
calanus, next in importance, barnacle (Balanus) and bivalve larvae in smaller 
amounts, and with unicellular forms, as just noted (curiously enough, out of about 
1,000 specimens 8 to 15 millimeters in length over 700 contained no food); while 
the young mackerel had eaten copepod nauplii (chiefly Calanus and Temora) and 
crustacean (probably copepod) eggs, with a few ostracods, euphausiid larvae, and 
even young fish. 
In Norwegian waters, according to Nordgaard. (1907), the older herring feed 
chiefly on euphausiids and copepods, especially the genera Calanus and Temora, 
with ostracods, tintinnids, larval barnacles, Halosphtera, and other small members 
of the plankton consumed in smaller amounts. Copepods and euphausiids together 
constitute almost the entire diet of the herring in the Gulf of Maine, with fish smaller 
than about 4 inches long taking chiefly the former and larger ones taking both at 
localities where they are available (Moore, 1898; Bigelow and Welsh, 1925, p. 103). 
Young herring, taken while feeding on the surface at Woods Hole, have been found 
full of copepods of several species. What is known of the feeding habits of the 
alewife ( Pomolobus pseudoharengus) , and blueback ( Pomolobus sestivalis) , is to the 
effect that they also subsist chiefly on these two groups of Crustacea during the part 
of the year when they are in salt water, and that shad ( Alosa sapidissima ) subsist 
on copepods and mysid shrimps. Mackerel, in the Gulf of Maine, have also long 
been known to feed greedily on calanoid copepods (the "red feed” or "cayenne” of 
which fishermen often describe the fish as crammed full). I have found fish, taken 
off Cape Elizabeth, August 12, 1912, packed with Calanus jinmarchicus and Pseudoca- 
lanus elongatus; Goode (1884a) found the stomachs of mackerel, taken off Portland in 
1874, full of large copepods and euphausiids. The schools of mackerel frequenting 
the Bay of Fundy have also been reported as following and pre 3 nng upon the shoals of 
50 So far as I can learn the^e is no record of the stomach contents of the larval witch (Glyptocephalus) or American plaice 
(Hippoglossoides). 
