ART. 15 COPEPOD CRUSTACEANS OF CHESAPEAKE BAY WILSON ] ?> 



bay it was more of a winter species and was found only during tbt. 

 winter at the stations of the extreme inner end of the bay. Tht 

 largest number of specimens in any one haul was 1,500, obtained lu 

 October at Station H. The number of specimens of this species 

 diminished steadily in going up the bay and toward the inner end 

 were reduced so low as to be unworthy of a percentage mark, onl;^ 

 one or two being found in some winter hauls. It was common botii 

 at the surface and probably near the bottom in the outside ocean 

 during August. 



Pseudocalanus was more of a winter species in the outer bay and 

 a spring species in the inner bay. Its seasonal distribution, how- 

 ever, was not well defined anywhere, and it was apparently likely U^ 

 appear in small numbers during any month of the year and in •aw. 

 part of the bay. 



PseudodiaptoTivas was a decidedly winter form throughout the ba.7/. 

 It was nowhere very abundant, but proved to be the exact reverse, 

 of Paracalanus^ its numbers increasing in going up the bay and 

 reaching their maximum at Station Z, with Station V a close sec- 

 ond. In the outer bay its numbers were reduced below a percentage 

 value at several stations. This species was reported as a summer 

 form in Narragansett Bay by Williams and in the Woods Hole 

 region by Fish. Fish stated, however, that it was not a true sunj- 

 mer species, but served as a connecting link between the summei 

 and winter copepods. Sharpe reported it from Sheepshead Bay 

 N. Y., in September. In Chesapeake Bay it seemed to appear iii 

 summer in small numbers, continued through the autumn, reached 

 its maximum early in winter, and then lasted into early spring at :; 

 few stations. 



The species thus far considered are the 10 that Avere universalh 

 distributed. Of the others Galanus -ftninarchicus appeared only \v. 

 the outer bay and during the winter. It was found, however, ii: 

 goodly numbers in the outside ocean during August. 



Ectinosoma curticoi^ne was a winter species, especially in the inner 

 bay, where it was much more abundant than in the outer bay. Eury- 

 temora atnericana was found only in winter, except at the extreme' 

 inner end of the bay, where it appeared in March at Stations W 

 and Z. The second species, hirundoides, was obtained chiefly during- 

 winter in the outer bay and during spring in the inner bay. Th< 

 number of specimens taken increased decidedly in going up the 

 bay. Both species of this genus were obtained by Williams in Nar- 

 ragansett Bay, but he did not give the seasonal distribution. Sharpen 

 found hirundoides at Woods Hole in July, while Fish listed it as ik 

 winter form continuing into the spring. 



Microthalestris appeared during every season of the year in the 

 outer bay but was confined to winter and spring in the inner bay. 



