PROGRESS IN BIOLOGICAL INQUIRIES 



41 



almost all of the small crustaceans living in the littoral zone. As 

 the temperature rises in June they leave the shallow water and seek 

 deeper levels. By August 1 of the past year this zone was entirely 

 vacated as far north as Boothbay, Me. During that month and 

 September more than 50 seine hauls, extending from Mount Desert 

 to Provincetown, yielded but three cod, although scattering pollock 

 were often taken. Just where the young cod go after entering the 

 deep waters has not yet been determined. Hauls made over the 

 whole area with the Petersen trawl at all levels did not yield a single 

 cod, although three small haddock were taken at 30 meters. Had- 

 dock apparently never enter the shore zone, remaining always in 

 the deeper waters. 



Doctor Fish is being assisted in Massachusetts Bay by Robert A. 

 Goffin and Richard Parmenter, and in the Gulf of Maine by Capfc 

 George Greenleaf, master of the Gannet. Marie D. P. Fish also is 

 aiding in the identification of the larval fish. 



A report on the plankton taken on a three weeks' cruise off New- 

 foundland in June, 1924, and a report on a hydrographical and 

 plankton section extending from Gay Head to the Gulf Stream, made 

 on the Halcifon in August, 1924, will be completed during the sum- 

 mer of 1925!^ 



This investigation of the early history of the cod is designed to 

 supplement and complete the study of the adults, which has been 

 under way for the past two years. The study of the adults includes 

 extensive tagging experiments testing the migrations and growth 

 and scale examinations. The work has been conducted by William 

 C. Schroeder, with the advice and aid of Dr. Henry B. Bigelow of 

 Harvard University. Doctor Bigelow's interest has done much to 

 make the investigations a success. 



The tagging operations connected with this investigation were 

 brought to a close for the calendar year when the Halcyon completed 

 her final cruise on October 28. During 1923 operations extended 

 from April 17 to October 17, and during 1924 from July 12 to 

 October 28. The progress of the investigation from its beginning 

 in April, 1923, until November 24, 1923, may be summarized as 

 follows : 



During 1923 about 98 per cent of the fish Avere tagged on Nan- 

 tucket Shoals in the general region of Great Round Shoal whistling 

 buo}'. The remaining 2 per cent were tagged off No Man's Land, 

 Pollock Rip, Chatham, and on Stellwagen Bank. 



Oi3erations during 1924 were more extended, and a large part of 

 Jie fish was tagged off the coast of Maine. The catch was divided 

 as folloAvs: Nantucket Shoals, 4,384 fish; Massachusetts, north of 

 Cape Cod, 163 : New Hampshire, 8 ; Maine, 5,793. 



