PROPAGATION AND GROWTH OF HERRING. 659 



its spawning is thus described : " Gathered in dense schools, the spawners 

 and milters move slowly in a circle, the dorsal fins often protruding above 

 the surface of the water. Suddenly, as if struck by an electric shock, 

 they dart off, and immediately roe and milt are expelled in the water. 

 Wherever there is only one coujile they slowly swim in a circle, the milter 

 holding his head close to the pectoral fin of the spawner." ^"^ Although 

 the roe is not loose, it is only a little heavier than the water of the river, 

 so that by artifical impregnation it can be kept floating in the current; 

 it also differs fi'om the roe of the herring by being entirely free from any 

 sticky substance, by which it could be fastened to any object either at the 

 bottom or near the siu-face. With a water temperature of 24P C. ( 75.2° F.) 

 it is hatched in about 60-70 hours, but when the temperature is lower it 

 takes longer, requiring about seven days with a temperature of 62.6^- 

 64^.4 F. ^'^ For a spawning-place the shad prefers either coarse sand or 

 a bottom with a rich vegetation. ^"^ The Alosa prwstahilis does not reach 

 its maturity until it is 3-4 years old, although milters which are only 2 

 years old are said to be able to propagate the species. ^°'' When five 

 years old they are considered fully grown.^"^ 



The American river-herring {Pomolohus pseudoharengus — " the alewife") 

 seems to reach maturity at the same age as the Alosa prcvstahilis^^'^, but its 

 roe when ejected is like that of the herring, accompainied by a sticky 

 slime, by means of which it adheres to any objects found in the spawning- 

 place ; it is hatched at the usual temperatare in about 70-74 hours.^^^ 



Our common Alosa finta also spawns up rivers and streams, where it 

 empties its sexual organs with violent muscular exertions, beating the 

 water with its tail, so that during quiet evenings or nights the noise of the 

 spawning may be heard at some distance from the spawning-place."^ 



105 Report of the Commissioners of Fisheries of Massachusetts, for 1869, p. 17. — Slack, 

 United States Commission Fish and Fisheries, II, report for 1872 and 1873, p. 460. 



"'e Report of the Commissioners of Fisheries of Massachusetts, for 1867, p. 36. — United 

 States Commission, Fish and Fisheries, II, pp. 425, 430. 



^"^ Slack, United States Commission, Fish and Fisheries, II, p. 460. 



'"» Report of the Commissioners of Fisheries of Massachusetts, for 1867, pp. 23, 40; for 

 1869, p. 18; for 1870, p. 5; for 1871, p. 12; for 1873, p. 18 ; for 1875, pp. 5, 52. 



109 Report of the Commsssioners of Fisheries, of Massachusetts, for 1869, p. 21. 



110 Report of the Commissioners of Fisheries of Massachusetts, for 1868, pp. 7, 8, 9, 

 23; for 1869, pp. 5, 6, 21 ; for 1874, p. 8 ; for 187.5, p. 52.— United States Commission of 

 Fish and Fisheries, II, pp. LIX-LXI. 



111 Report of the Commissioners on Inland Fisheries of Massachusetts, for 1873, pp. 

 8, 9. 



II* Yakrell, "British Fishes," 3d ed., I, p. 130.— KrOyer, "Danmark's Fiske," III, 

 pp. 317, 318. 



