BIGELOW: COAST WATER EXPLORATION OF 1913. 271 



portion of warm water animals, and loggerhead turtles, sharks, and 

 pilot fish were seen on the surface. And the deep haul contained many 

 oceanic species, e. g., Criseis, Corolla, Firoloides, Liriope, Aglaura, 

 Rhopalonema, Agalma elegans, and the tropical hydromedusa Niobia, 

 which, owing to its asexual budding, comes into the oceanic category 

 so far as its dispersal is concerned. But there were also many neritic 

 forms, e. g. fish eggs and fry, stomatopod larvae, gammarids, young 

 crabs, and the ctenophore Pleurobrachia. Five miles nearer land the 

 water was crowded with copepod larvae and the ctenophore Mnemi- 

 opsis, though still with an occasional Agalma, Doliolum, and Liriope. 

 The swarm of Mnemiopsis, which revealed its presence by its phos- 

 phorescence (for we ran through it at night) as well as by an occasional 

 use of the dip net, was some twenty miles broad. But as land was ap- 

 proached it gave place to hosts of Salpae, which filled the surface waters 

 at Station 10075. At this Station we noted an occasional Cyanea, and 

 Aequorea, and many large specimens of Bcroe forskalii, besides schools 

 of menhaden (Brevoortia) and porpoises (Tursiops). 



The final Gulf Stream Station (10076) lay abreast of Chesapeake 

 Bay. And though the plankton consisted chiefly of the same oceanic 

 forms which were encountered further north, the presence of stomato- 

 pod larvae, Aequorea, considerable numbers of small copepods, and eel 

 grass (Zostera) instead of Sargassum floating on the surface, showed 

 as clearly as did the salinity (p. 200) that the influence of the fresh water 

 from the Bay was felt over the whole breadth of the continental shelf. 

 And perhaps this also explains the fact that all the hauls at this 

 Station were scanty, and contained a large proportion of debris. 



As the mouth of the Bay (Station 10077) was approached the macro- 

 plankton grew even more scanty, though there was a decided increase 

 of microplankton (p. 334) ; and Beroe was once more found in consider- 

 able numbers, together with the neritic hydromedusa Laodicea, while 

 a new element of shore origin was added by swarms of larvae of the 

 blue crab (Callinectes) on the surface. The few oceanic elements 

 were now much in the minority; but even near the mouth of the Bay 

 (Station 10078), the nets yielded a' few Liriope and an occasional 

 siphonophore (Diphyes) . 



The stations on the run northward to Cape Cod all lay close to land, 

 hence yielded chiefly neritic plankton. The swarm of Callinectes 

 larvae extended for about thirty-five miles along the coast, being no 

 doubt recruited from the various bays and inland sounds, as well as 

 from the Chesapeake itself; but it had disappeared by the time Station 

 10079 was reached, and it is interesting to note that its disappearance 



