32 bulletin: museum of comparative zoology. 



PAGE. 



Meganyctiphanes norvegica . . . . . . .118 



Euthemisto compressa . . . . . . . . .119 



Clione limacina 119 



Limacina balea 120 



Salpae 121 



Tomopteris helgolandica 121 



Chaetognaths . . . .121 



Medusae 123 



Siphonophores 125 



Ctenophores .......... 126 



Results of the quantitative hawls 127 



Microplankton . 130 



Table of stations .......... 135 



Table of temperatures ......... 137 



Table of salinities .......... 137 



Table of densities . . 141 



Table of current measurements . 143 



Bibliography . . . . . 145 



Explanation of plates. 



The cruise. 



During July and August 1912 the U. S. Fisheries Schooner Gram- 

 pus was detailed for an oceanographic cruise in the Gulf of Maine, 

 under my direction, the purpose being to make as nearly complete 

 a survey of the temperatures, salinities, currents, and plankton, of the 

 waters of the Gulf as the brief time at our disposal, and the limitations 

 incident to the use of a sailing vessel would allow, (Bigelow, 1913). 

 It was also planned to do some systematic trawling in the neighbor- 

 hood of Casco Bay, in cooperation with the Harpswell Marine Lab- 

 oratory. During the cruise I was accompanied by Messrs. W. W. 

 Welsh and Herbert E. Metcalf as assistants. It is a pleasure, to ac- 

 knowledge the assistance which Dr. CO. Esterly has afforded in the 

 preparation of this report, by identifying the copepods in more than 

 60 samples of plankton, no small task. And the value of the dis- 

 cussion of the plankton (p. 98) is largely due to his efforts, for copepods 

 were altogether its most important constituent. A like debt of thanks 

 is due to Mr. E. L. Michael, who has identified many of the Sagittae 

 (p. 121), and to Mr. W. W. Welsh, who supplied the lists of fish fry 

 and adult fishes (p. 107). I am also indebted to Capt. John W. McFar- 

 land, of Gloucester, who made several "tows" from his Schooner 

 Victor. 



