4O2 BULLETIN OF THE BUREAU OF FISHERIES. 



Many of the algae growing in the localities noted above are covered with mud and have a 

 pale, sickly appearance. Under such conditions it is not surprising that the number of 

 species and individuals is small. 



It is surprising, however, that the algae were not more abundant in Pamlico Sound 

 at Ocracoke. Here are several jetties and piles of shells that would seem to furnish 

 excellent habitats for algae. Ocracoke Inlet (leading directly to the open ocean) is only 

 2 km. away, and the water is not more turbid than around the laboratory in Beaufort 

 Harbor; yet only 14 species were found there, the majority of the species that are 

 dominant in Beaufort Harbor being entirely lacking. This scarcity may be due in part 

 to th*e low density observed there, but further studies are needed to explain these facts. 



The algae collected in Newport River near "Green Rock" were, with the exception 

 of Gelidium, mostly unattached. These seem to be plants that have been brought here 

 by the tide and are continuing their existence floating near the bottom. 



It is worthy of note that, with the exception of fragments of Enteromorpha, etc., on 

 the sand breaks at Fort Macon and Shackleford, no algae were ever observed during the 

 Summer growing on wood in Beaufort Harbor. Although there are numerous wharf, 

 beacon, and railroad piles and two plank walls here with algae attached to shells and 

 stones near their bases, not a single specimen of algae, not even Lyngbya, was ever found 

 on these. In North River, Core Sound, and Pamlico Sound, on the contrary, there were 

 found abundant Lyngbya and several plants of Enteromorpha, Ectocarpus, Dictyota, 

 and Hypnea on the piles of wharves and beacons, and in the spring Enteromorpha, 

 Porphyra, and other algae grow abundantly on the wharf piles in Beaufort Harbor. The 

 reason for this is not apparent, but it seems probable that it is caused by the crowding 

 out of the algae by sponges, barnacles, ascidians, and other animals which grow abun- 

 dantly on these piles. 



In no case have there been observed large numbers of animals and algae growing 

 together, the parts of both rocks and buoys which bear a conspicuous growth of algae 

 being comparatively free of animals and vice versa. Studies on this point would probably 

 yield some interesting data. 



OTHER LOCALITIES. 



i 



No extended studies have been made at any place other than Beaufort, but the 

 observations made indicate that other localities, while differing considerably in detail, are 

 affected by the same general factors as at Beaufort. With some exceptions the algae are 

 confined to the zone below low-tide line, they extend scarcely more than 90 cm. below low 

 water, and they have to endure great turbidity. At no place, however, was there found 

 anything approaching the number of species or of individuals observed at Beaufort. 

 This seemed especially surprising in the case of Charleston, S. C., since a considerable 

 number of species has been reported from this place by earlier collectors. Three days at 

 different times during July and August were, however, spent in a careful search of this 

 harbor, including James Island, Morris Island, Isle of Hope, and Isle of Palms, without 

 revealing a large number of species or of individuals. While the records below were 

 obtained from observations made on short visits to each place, they represent from one 



