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bulletin: museum of compaeative zoology. 



Meganyctiphanes norvegica 



Euthemisto compressa . 



Clione limacina 



Limacina balea 



Salpae .... 



Tomopteris helgolandica 



Chaetognaths 



Medusae 



Siphonophores 



Ctenophores 

 Hesults of the quantitative hawls 

 Microplankton 

 Table of stations 

 Table of temperatures 

 Table of salinities 

 Table of densities 

 Table of current measurements 

 Bibliography 

 Explanation of plates. 



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118 



119 



119 



120 



121 



121 



121 



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145 



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, anfl 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. C. O. 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. 



