n] OF ANTHOCYANINS 25 



been insufficiently watered. Miyoshi (375) has observed that leaves 

 of trees in the East Indies, Ceylon and Java redden during the 

 dry period in the same way as autumnal leaves in the temperate 



regions. 



8. In High Alpine plants there is undoubtedly, on the whole, a 

 much stronger development of anthocyanin in all the parts stem, 

 leaves, bracts and flowers, than in plants growing in lowland regions. 

 Gaston Bonnier (294, 307) has made observations upon this point, and 

 has found that the flowers of many species are more highly coloured, 

 the greater the altitude. Kerner (398) also remarks : ' The leaflets and 

 stem of the Alpine Sedum atratum, those of Bartsia alpina, and, above 

 all, numerous species of Pedicularis (e.g. Pedicularis incarnata, rostrata, 

 recutita) are coloured wholly purple or dark violet. ...It is also a very 

 striking phenomenon that widely-distributed grasses (e.g. Aira cccspi- 

 tosa, Briza media, Festuca nigrescens, Milium effusum, Poa annua and 

 nemoralis), which in the valley possess pale-green glumes, develop 

 anthocyanin in them on lofty mountains, so that there the spikes 

 and panicles exhibit a deep violet tint, and on this account the regions 

 in which grasses of this kind grow in great quantities receive a peculiar 

 dark colouring.... The same occurs in the numerous sedges and rushes 

 growing in the Alps, which have dark- violet, almost black, scales covering 

 the flowers (e.g. Carex nigra, atrata, aterrima, Juncus Jacquinii, trifidus, 

 castaneus)....It is known that the floral-leaves of many plants growing 

 on lofty mountains, and in the far north, are coloured blue or red by 

 anthocyanin, whilst in the same species, growing in warm lowlands 

 and in southern districts, they appear white. Particularly noticeable 

 in this respect are the Gypsophyllas (Gypsophylla repens), the Carline 

 Thistle (Carlina acaulis), the large-flowered Bitter-cress (Cardamine 

 amara), the Milfoil (Achillea Millefolium), and many of those Umbelli- 

 ferae which have a very wide distribution, and occur all the way from 

 the lowlands up to a height of 2500 metres in the Alps, such as Pim- 

 pinella magna, Libanofis montana, Chaerophyllum Cicutaria, and Laser- 

 pitium latifolium." And again: 'The flowers of species grown in the 

 Alpine garden on the Blaser at a height of 2195 metres above the sea 

 exhibited, as a rule, brilliant floral tints, and some were decidedly 

 darker than the flowers grown in the Vienna Botanic Garden. Agro- 

 stemma GitJiago, Campanula pusilla, Dianthus inodorus (sylvestris), 

 Gypsophila repens, Lotus corniculatus, Saponaria ocymoides, Satureja 

 hortensis, Taraxacum officinale, Vicia Cracca, and Vicia sepium are 

 good examples of this. Several species, which produced pure white 



