1194 FISHERIES OF THE UNITED STATES. [40] 



Sea-bass. — Gentropristis nigricans. 



(.varies. Wood's Holl, Mass., May 26, 1872. 10,532. Viual IS". 

 Edwards. This species spawns on the coral banks and rocky 

 ledges of the Atlantic coast, some miles from shore, in spring. 

 The spawning grounds extend from the CarolinastoCape Cod. 



Spring alewife. — Clupea vernalis Wilson. 



Ovaries. Wood's Holl, Mass., April, 1871. 10,615. Yinal N. Ed- 

 wards. Immense schools of this species ascend the larger 

 rivers of the Atlantic coast in springs for the purpose of spawn- 

 ing. The principal spawning-grounds are in the tributaries of 

 Delaware and Chesapeake Bays, and Albemarle and Pamlico 

 Sounds. 



Cod. — Gadus morrhua Linn. 



Ovaries. Wood's Holl, Mass., April 20, 1871. 10,616. Vinal N. 

 Edwards. The spawning-grounds of the codfish off our own 

 coast extend as far south as Central New Jersey. The princi- 

 pal spawning-grounds are off the coasts of Maine and Massa- 

 chusetts and on the more distant fishing banks. Eipe fish may 

 be seen at any time between September and the following May, 

 though the height of the spawning season occurs in mid-win- 

 ter. The number of eggs in a fish varies with the size of the 

 parent — a 75-pound female containing about 9 millions. The 

 eggs hatch in from 13 to 50 days, according to the temperature 

 of the water. They are ^ of an inch in diameter, and have 

 a specific gravity slightly less than that of sea- water. 



Common flounder. — Pleuronectes americanus Walbaum. 



Ovaries. Wood's Holl, Mass., April 3-5, 1876. 15,186. IT. S. Fish 

 Commission. The spawning-grounds for this species on the 

 coast extend from Maine to Cape May, or perhaps even farther 

 south. The spawning season occurs during the summer months. 



Sand flounder. — Bothus maculatus (Mitch.) J. & G-. 



Ovaries. Wood's Holl, Mass., June. 15,187. Vinal 1ST. Edwards. 

 This species spawns in summer along the coast of Southern 

 New England and New Jersey. 



Tomcod. — Microgadus tomcod (Walb.) Gill. 



Ovaries. Wood's Holl, Mass., January 10, 1874. 15,191. XL S. 

 Fish Commission. This species spawns in the salt and brack- 

 ish waters of the New England coast in mid-winter. 



Sea-raven. — Hemitripterus Jiispidus (Schn.) Goode. 



Ovaries. Casco Bay, Me., August 25, 1872. 15,203. U. S. Fish 

 Commission. This species spawns in the shoal waters of New 

 England in the fall. 



