408 BULLETIN OF THE BUREAU OF FISHERIES 



of Maine, where they are caught from docks and bridges and in salt creeks, etc., in 

 summer as well as in winter. Tomcod, for instance, are common in the inner parts 

 of Duxbury Bay in midsummer though most other fish move out then to avoid the 

 heat, and there are also plenty of them in a certain brackish stream at Cohasset at 

 all seasons, which applies to many similar locations all up and down the coast, 

 including the Bay of Fundy, where, as Huntsman (1922a) remarks, tomcod are in 

 the estuaries, not outside, at all seasons. They are so resistent to cold as well as 

 to heat that we find no record of them killed by winter chilling, a fate that sometimes 

 overtakes other fishes living in shoal water, and they are equally hardy toward 

 sudden changes of salinity. 



Food. — Tomcod feed chiefly on small crustaceans, particularly shrimps and 

 amphipods, a great variety of which have been found in their stomachs; also on 

 worms, small mollusks, squids, and fish fry. Of the latter Vinal Edwards noted 

 alewives, anchovies, cunners, mummichogs, herring, menhaden, launce, sculpins, 

 silversides, smelt, and sticklebacks in tomcod stomachs at Woods Hole. 



According to Herrick 71 tomcod are not as keen-sighted as pollock nor as active 

 as hake, spending most of their time quietly on the bottom in the aquarium ; but his 

 experiments proved that they are able to recognize concealed baits by the sense of 

 smell if they chance to swim near, and that they search the bottom, swimming to 

 and fro with the chin barbel and sensitive tips of the ventral fins dragging, finding 

 food by touch, or, as we suspect, to stir up shrimps, etc. 



Breeding habits. — This fish spawns in the shoal waters of estuaries, stream 

 mouths, etc. — in salt or in brackish water indifferently — and its eggs have even 

 been hatched artificially in fresh water. The season lasts from November to 

 February, inclusive, with the height of production in January. The eggs are 

 about 1.5 mm. in diameter with conspicuous oil globule, and unlike those of its 

 larger relatives they sink to the bottom where they stick together or to seaweeds, 

 stones, etc., in masses. Incubation occupies about 24 days at an average tempera- 

 ture of 43°; 30 days at 40°. The larvas are not only considerably larger (5 mm.) 

 at hatching than those of the cod, but further advanced in development, the mouth 

 being formed; and they differ from all other Gulf of Maine gadoids at a correspond- 

 ing stage by the presence of the oil globule and by the fact that the vent opens at 

 the margin of the ventral fin fold and not at its base at one side. 72 Although great 

 numbers of tomcod have been hatched artificially by the State of New York its 

 late larval stages have not been described nor have we seen them ourselves. The 

 fry, which are said to remain through their first summer in the waters vdiere they 

 are hatched, reach a length of 2}4 to 3 inches by the following autumn, but nothing 

 is known of the rate of growth of older fish. 



Commercial importance. — The tomcod seems to have been more highly con- 

 sidered as a food fish three-quarters of a century ago, when between 5,000 and 10.000 

 pounds were caught annually in the Charles River near Boston alone, than it is 

 to-day when 1,000 pounds is a fair average for tomcod brought into Boston annually. 

 In 1919 the reported catch was only about 900 pounds for the west coast of Nova 



•i Bulletin, United States Fish Commission, Vol. XXII, 1902 (1904), p. 262. 



" Ryder (Report, United States Commissioner of Fish and Fisheries, 1885(1887), p, 523, PI. XIII, fig. 67) describes the 

 newly hatched larva. 



