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APPENDIX 



growing in a large pot containing a shrub some young plants of this 

 species. I had been in the habit of mixing Sphagnum with soil 

 for potting purposes, and evidently the plant had been introduced 

 in this way in the previous autumn. As the soil-conditions were 

 very much drier than those of the boggy ground in which the species 

 normally grows, I resolved to note their effect on the young plants 

 in question. 



During the summer of 1906 they developed a trailing habit, the 

 main stems, seven inches long with secondary leafy shoots two inches 

 in length, hanging over the sides of the pot. Through the winter 

 they remained in the same leafy state, and in the spring rapid growth 

 took place, so that by July 1907 the main stems were seventeen 

 inches in length (three inches in the pot and fourteen inches hanging 

 over), the secondary shoots or branches being proportionately long. 

 Flowering now occurred, and the pot draped all around with the 

 hanging stems formed quite a pretty spectacle. It remained thus 

 until the autumn, when I went abroad and the experiment ended. 

 The experiment was repeated in November 1912, when I put some 

 other plants in an ordinary pot of soil and kept them in the same 

 conditions as before. After flowering in midsummer the plants 

 began to trail over the sides of the pot, producing stems about six 

 inches long. When in the Azores, I watched carefully on the moors 

 for evidence of this trailing habit, but only found a tendency in this 

 direction in the case of plants growing in drier conditions on the sides 

 of banks. 



The leaves in these experiments were much larger than with the 

 typical growth, 7x6 mm. instead of 3 x 2*5 mm. The usual 

 winter leaf of the normal plant is particularly small, 2 to 3 mm.; 

 whilst the summer leaf is as a rule markedly larger; but I found 

 that this is only indirectly due to the season. In November of two 

 different years I noticed that the typical small leaves were produced 

 when the plant lay flat on the oozy mud or on a level patch of boggy 

 ground, which would be usual in winter. In places, however, where 

 the plants were creeping over loose-growing Sphagnum or clambering 

 over stocks of Carices, under circumstances where the lower leaf- 

 surfaces were freely exposed to the air, the size of the leaf was 

 increased to between 4 and 6 mm. 



The interesting point in these observations is that the plants in 

 the first experiment assumed the habit of growth of Anagallis filifor- 

 mis (Ch. and Schl.), where the stems attain a length of eight inches 

 (20 cm.). This is a peculiar extra-tropical South American species 

 growing in sandy and moist places in South Brazil (Primulacea? by 

 Pax and Knuth, Pflanzenreich, 1905). Although at first regarded 

 as a distinct species of the Tenella group of the genus, it is viewed 

 in De Candolle's Prodromus as only a variety of Anagallis tenella ; 

 and it is noteworthy that the species just named is not known either 

 from South or from North America. The essential differences are 

 slight, and are chiefly concerned with the degree of woolliness of the 

 filaments and with the extent of the adhesion in their lower part. 

 The stamens of the flowers were especially examined only in the 

 second experiment, and displayed the characters of those of A. 



