MARINE ALGJ& OF BEAUFORT, N. C. 

 FLORA OF CORAL REEFS. 



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The flora of the coral reefs is predominantly southern, of the 47 identified species 

 and varieties found there (Table 2), 32 (68.1 per cent) being recorded for the Florida- 

 West Indies region and 14 (29.8 per cent) being known from New England. 



Comparing the three collections made on the principal reef, we find the species 

 occurring as follows : 



This southern relationship is more striking when it is" remembered that the visit 

 to the reef in May was made at a time when Beaufort Harbor bore the spring flora, 

 having 90.5 per cent of the species common to New England and only 33.3 per cent of 

 the species common to the Florida- West Indies region. At this time several northern 

 species which occur in this locality only in the spring were found on the reef. The 

 small proportion of the species collected in August, 1914, which are common to other 

 regions is due to the fact that four of these are new, while six are new to North America. 

 If these species are excluded, the figures are New England 40 per cent, Florida- West 

 Indies 100 per cent. Similarly, if two species new to North America collected in July 

 and August, 1915, are excluded, the figures for this period are New England 50 per 

 cent, Florida- West Indies 100 per cent. It could not be illustrated more forcibly that 

 this flora is southern in its nature and that the species which are common to New 

 England are those which are generally distributed and occur along the entire coast. 



On all trips there were obtained from this reef species which were not found 

 growing elsewhere in this region. In May, 1907, ten such species were observed, eight 

 being distinctly southern, one being distinctly northern, and one being generally 

 distributed. In August, 1914, there were observed, besides the ten species that are 

 new or new to North America, eight species not found elsewhere in this region, seven 

 being distinctly southern and one being generally distributed. In July and August, 

 1915, there were collected, besides the two species that are new to North America, 

 nine species not found elsewhere in this region, seven being distinctly southern and 

 two being generally distributed. It is thus seen that the flora that in this region is 

 confined to the reefs is overwhelmingly southern in its relationship. Only four identi- 

 fied species were found in all three collections from the reef, while 14 were obtained in 

 two collections, and 29 were found only once. This is probably an indication not so 

 much of a seasonal distribution as of the abundance of the species occurring there and 

 our ignorance of them. It is highly desirable that a thorough study of these reefs be 

 made. 



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