96 



BULLETIN OF THE BUREAU OF FISHERIES 



late in the fall, with the heaviest runs in July, August, and the first part of September, 

 though Doctor Huntsman writes that in 1917 the season lasted only from early 

 August to early October. In Mac-bias Bay, near by, herring spawn at about the same 

 season, that is, from mid- July until the end of September. Passing thence westward 

 we find the breeding period progressively later and shorter — mid-August until 

 October about Petit Manan and near Mount Desert; mid-September until the end 

 of October near Casco Bay and off Wood Island; September 20 until about Novem- 

 ber 1 in Ipswich Bay; 87 the month of October in Massachusetts Bay; while west of 



Fig. 42. — Larval stages of the herring (Clupea harengus). After Ehrenbaum 

 a. Newly hatched, 7 millimeters. l>. 10 millimeters, c. 19 millimeters, d. 29 millimeters, e. Fry, 41 millimeters. 



Cape Cod the herring do not begin to spawn until mid or late October, with the major 

 production of eggs about the 1st of November. Thus, while spawning occupies 

 three months at the mouth of the Bay of Fundy it lasts hardly longer than one 

 month in the southwestern part of the Gulf besides commencing some three months 

 later in the year. 



Temperature at which spawning taJces place. — Thanks to the considerable num- 

 bers of serial observations taken in the Gulf by the Grampus during the past 10 

 years and in the Bay of Fundy by the Biological Board of Canada, it is now possible 

 to establish the temperature at which herring spawn in our waters more closely than 



" Allen. Memoirs, Boston Society of Natural History, vol. 8, No. 2, 1916, p. 201, fide E. K. Haskell, of Ipswich, Mass. 



