42 bulletin: museum of comparative zoology. 



Oceanography. 



Up to the present time no systematic studies of the oceanography 

 of the Gulf of Maine have been undertaken. The surface tempera- 

 tures have, of course, been known in a general way for many years, as 

 has the existence of a cold band of water close to the coast of Maine 

 and in the Bay of Fundy; and thanks to Dickson's, (1901) researches 

 we have a fairly satisfactory idea of the seasonal range of surface tem- 

 perature for two years, 1896 and 1897. But his records were far too 

 few to delimit the distribution of slightly differing temperatures within 

 the Gulf. 



Almost all the knowledge we possess as to the bottom temperatures 

 dates back to 1872, 1873, and 1874 when a series of dredgings was 

 carried out by the U. S. Fish Commission and the U. S. Coast Survey 

 on George's Bank, in the Bay of Fundy, off Cape Elizabeth, and at 

 various other localities in the Gulf. The bottom temperature was re- 

 corded at each station, and the records have been published by Verrill, 

 (1873-1875); but unfortunately, as he himself points out, the Miller- 

 Casella thermometers which were used proved unreliable, two instru- 

 ments often differing by several degrees when used simultaneously. 

 Nevertheless the results were valuable as showing in a general way 

 the low bottom temperature of the Gulf (p. 93). So far as I can learn, 

 no intermediate temperatures have ever been taken in the Gulf, except 

 a few which I obtained during the summer of 1911 between Cape 

 Ann and Casco Bay. 



The salinity records for the Gulf are even more scanty than those 

 for temperature. A considerable number of hydrometer readings for 

 the surface have been taken by the Bureau of Fisheries ; but most of 

 them were made with unstandardized instruments, and under circum- 

 stances precluding any approach to accuracy. The only reliable 

 salinity records from the surface are three titrations by Dickson, 

 (1901), of samples collected off Cape Cod, April, 1896; off Cape Sable, 

 April, 1896; and northeast of George's Bank, April, 1896. And there 

 are no records whatever of the salinity on the bottom, or at inter- 

 mediate depths. 



For George's Bank and the Eastern Channel, the data is rather more 

 extensive, there being eighteen titrations (Dickson, 1901); and a 

 considerable series of temperatures were taken by the Albatross in 

 1883 in the channel with Negretti and Zambra reversing thermometers. 

 There is one titration from Brown's Bank and a considerable number 



