. Bulletin. Science; Natural history; Natural history. A » = BEST 56-9 â c = C A = L. A. 68-70 Figure 4. Total scores for various non-taxonomic groups of species compared for: A â Dawson's 15 best stations outside the Los Angeles area; B â the 15 stations in the Los Angeles area in the period 1956-9: and C â the same stations as B in the period 1968-70. Seasonal variations â Nevertheless. I have the subjective impression that conspicuous seasonal variations, at least in quantity, do occur in the algal flora, with a maximum in late spring and a minimum in late summer. There are three
. Bulletin. Science; Natural history; Natural history. A » = BEST 56-9 â c = C A = L. A. 68-70 Figure 4. Total scores for various non-taxonomic groups of species compared for: A â Dawson's 15 best stations outside the Los Angeles area; B â the 15 stations in the Los Angeles area in the period 1956-9: and C â the same stations as B in the period 1968-70. Seasonal variations â Nevertheless. I have the subjective impression that conspicuous seasonal variations, at least in quantity, do occur in the algal flora, with a maximum in late spring and a minimum in late summer. There are three possible ways in which such a variation could exist and not appear in the test. First, shifting sand appears to be the major factor in variation (Dawson. 1965a: 225). If this shifting is random with regard to season at any one station, it could obscure season- al variation. Second, the period of any variation, or differences from year to year in the time at which peaks occur, could be such that Dawson's division of the year into four seasons would not be precise enough to detect seasonal variation. Third, a summer flora of small species could replace a winter flora of large species, so that the number of species remains much the same while the total bulk of algae changes from season to season. These possibilities were tested by an investigation of the total scores given each entity for each month (Fig. 6). Data were used from all Dawson's station visits throughout southern California, and from the first visit made to each station in the present study. (It was thought that the inclusion of the second and third visits made in the present study would bias the data too much in favor of stations in the Los Angeles area). The distribution of station visits by month in the data used was found to range from 20 in November and 18 in January and February, to 2 in August and 4 in July and Septem- ber. Data from the earlier visit in August were added to those in July to make a 'mon
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