perennials, pscudoperennials, seasonal annuals, and aseasonal annuals. Perennials (species present as a 

 whole thallus throughout the year and persisting for more than one year) include Chondnis ch.spus, 

 Ascophyllum nodosum, and Fucus vesiculosus. Pseudoperennials (individual plants present throughout the 

 year but passing through adverse conditions in a reduced form) include Codium fragile. Seasonal annuals 

 (plants only found during part of the year) include Bangia atropurpurea, Desmarestia viridis, Cladophora 

 flexuosa, and Sphacelaria cirrosa. Aseasonal armuals (population as a whole present throughout the year 

 and capable of continual reproduction) include Uha lactuca and Enteromorpha flexuosa. 



Of the 1 58 species of benthic algae found in our area, several were site-specific or characteristic of 

 only one station (Table 1), such as Laminaria digitala at TT, Ceramium deslongchampii at GN, Fucus 

 spiralis at BP, Bryopsis plumosa at FE, Polysiphonia nigrescens at WP, and Gelidium crinale at FS. In 

 addition, some species are abundant at only 2 or 3 stations, e.g., Pilayella littoralis at GN and FS, and 

 Pra.uola stipilata at GN, TT, and SE. 



Temporal differences also occur, and seasonal components in the local flora have been identified. 

 Some examples include Bangia atropurpurea, Dumontia contorla, and Monostroma grevillei as most common 

 in winter-spring, Desmarestia viridis, Leathesia difformis, and Polysiphonia urceolata in spring-summer, 

 Champia parvula, Da.sya baillouviana, and Cladophora flexuosa in summer-autumn, and Callithamnion 

 tetragonum, Spermothamnion repens, and Sphacelaria cirrosa in autumn-winter (Table 1). 



The persistence of these spatial and temporal patterns, and their consistency from year to year is an 

 indication of the stability of the local flora. Another measure of stability is number of species, i.e., species 

 richness. 



The greatest number of species recorded from a single collection usually occurred in spring-early 

 summer for all stations. The most species collected in any month (1979-1985) was 1 17 in .July (Table 2), 

 and the fewest was 101 in March. TTie most species collected at any station since 1979 was l.'^l at BP 

 (Table ?i), and the least was 109 at both SF and TT. In each year, the greatest species number generally 

 occurred at WP (Table 4). 



When division proportions are analyzed by month and station, proportions are similar and independent 

 of species number (Tables 2 and 3), providing another measure of floral stability. Annual percentage of 



17 



