384 



BULLETIN OF THE BUREAU OF FISHERIES. 



The southern character of the species occurring on this reef is further shown by 

 the predominance of red algae. The total numbers found in the different divisions are : 



FLORA OF BOGUE BEACH. 



The flora which, in this locality, is found only on Bogue Beach (Table 3) is as 

 pronouncedly southern as is that of the coral reef. Of the 18 identified species and 

 varieties composing this list, 16 (88.8 per cent) are known from the Florida- West 

 Indies region, while only four (22.2 per cent) are recorded for New England. This 

 relationship is again shown by the predominance of red algae. The total numbers 

 found in the different divisions are: 



These facts support the suggestion previously made that most of these specimens 

 have been washed in from the coral reefs offshore or from the reefs lying to the south 

 of this locality, while some may have been brought by the Gulf Stream from the Florida- 

 West Indies region. 



CONDITIONS AT BEAUFORT, N. C. 



HARBOR. 



The principal factors affecting the growth and distribution of algae are temperature, 

 light, composition of the water, turbidity, movement of the water (including tidal 

 range), and the nature of the habitat. 



TEMPERATURE. 



The temperature of the surface water at the laboratory wharf (on Fivers Island) has 

 been taken at 5 p. m. almost daily during three periods, totaling almost four years. A 

 full statement of these figures is given in Table 9. A summary of the records, stated in 

 degrees centigrade, is as follows : 



