88 PROCEEDINGS OF THE NATIONAL MUSEUM vol.80 



Remarks. — Sars said of this copepod : " It is a pronouncedly littoral 

 species, being generally found in very shallow water, especially in 

 flat sandy creeks." R' and T were two of the shallowest stations in 

 the bay, the water measuring 7 and 9 meters, respectively, but S 

 was considerably deeper. In all three, however, the water was de- 

 cidedly brackish, especially at the surface, where these specimens were 

 obtained. In general, therefore, the conditions here in Chesapeake 

 Bay correspond favorably with those given by Sars. 



MACROSETELLA GRACILIS (Dana) 



Betella gracilis Dana, Wilkes Expedition, Crustacea, vol. 14, p. 1198, pi. 84, 

 fig. 3, a~g, 1853.— Wheelek, Bull. U. S. Bur. Fisheries, vol. 19, p. 188, fig. 

 24, 1900. 



Occurrence. — Nearlj' 100 specimens of this species were taken in 

 a surface net over a depth of 67 fathoms in the outside ocean ; none 

 were found within the limits of the bay. 



Remarks. — This copepod can be recognized at once by its linear 

 body and excessively long caudal setae. It is a true pelagic form and 

 is not likely to be found anywhere in the bay. 



MICROSETELLA NORVEGICA (Boeck) 



Setella norvegica Bobcic, Christiania Videnskebeliger Selskabet Forhandlinger, 



pi. 11, fig. 1 (9 figs.), 1864. 

 Microsetella norvegica G. O. Sars, Crustacea of Norway, vol. 5, p. 44, pi. 24, 



1904. 



Occurrence. — About 100 specimens, including both sexes, were ob- 

 tained in a vertical net at Station F on December 4, 1920, and 70 

 more in a surface net at Station E on January 22, 1921. 



Remarks. — From the distribution given by various authors this is 

 a very cosmopolitan species. According to Sars it is a true pelagic 

 copepod, always taken near the surface and usually at a considerable 

 distance from shore. Although it did not appear during the August 

 trip to the 100-fathom line, it is probably present there in winter 

 and early in spring, the season at which it was found at the mouth 

 of the bay. 



MICROTHALESTRIS LITTORALIS G. O. Sars 



Microthalc stria littoralis G. O. Sabs, Crustacea of Norway, vol. 5, p. 369, suppl. 

 pi. 11, fig. 1 (9 figs.), 1911. 



Occurrence. — This species was widely distributed throughout the 

 entire bay, but was nowhere abundant. The largest haul was at 

 Station T in a bottom net on March 29, 1921, from water 9 meters 

 deep over a muddy bottom. Here it constituted 1 per cent of a catch 

 that totaled 25,000, but its numbers were usually so small as to fall 

 below a percentage mark. 



