218 



OPENING OF THE PASSAGE TO THE INTERIOR OF THE FLOWER. 



Closing of Flowers at Upsala and Innsbruck. 



Name of Plant. 



Taraxacum officinale 

 Cichorium Intyhus ... 



Lactuca sativa 



Sonchus arvensis 



Sonchus oleraceus , 



Arenaria rubra 



Hypochoeris maculata 

 Hemerocallis fulva ... 

 Nymphcea alba 



Difference 

 IN Hours. 



5-6 

 4-5 

 3-4 

 2-3 



2 



1 



2 



1 

 2-3 



From a perusal of these tables it appears that flowers both open and close 

 earlier in the day at Upsala than at the more southerly situated Innsbruck. 

 This result, especially the earlier opening, is probably connected with the fact 

 that the sun during the flowering-season of the plants in question rises about an 

 hour and a half earlier at Upsala than at Innsbruck. 



With this difference in time of opening of flowers, the results of observations 

 carried out in mountainous districts on plants which extend from the low warm 

 valleys up into the hills entirely harmonize. The Hepatica {Anemone Hepatica) 

 blooms on the valley-floor at Innsbruck (560 metres) in March, at a time when the 

 sun rises at 6 a.m., its flowers opening each day between 9 and 10 a.m. In the 

 mountain glens, south of Innsbruck, at a height of 1560 metres above the sea-level, 

 it blossoms in May, at a time when the sun rises at 5 a.m. Here its flowers open 

 between 8 and 9 a.m. Lampsana communis and Sonchus arvensis blossom in July 

 in the meadows of the Innthal (560 metres); in the adjacent Gschnitzthal (660 

 metres higher) in August. The sun rises at Innsbruck in July at 4-30, and the 

 capitula of these two plants open in the Innthal between 6 and 7 a.m.; in August 

 the sun rises about an hour later, and the same plants open correspondingly in the 

 highly-situated Gschnitzthal also an hour later, i.e. between 7 and 8 a.m. 



Several ornamental garden plants are indefatigable in their blossoming. For 

 months on end flowers upon flowers are produced, only ceasing with the on-coming 

 of winter. As an example Catananche coerulea may be instanced; at Vienna it 

 remains in flower from the end of June till the end of October. Its capitula show 

 a periodic opening and closing, but they differ in the hour at which they execute 

 their movements according to the season. At the end of June and beginning of 

 July they open between 4 and 5 a.m., in August and in the first half of September 

 between 5 and 6, whilst in the latter part of September and beginning of October 

 they open between 6 and 7 a.m. Finally, in the widely-distributed Dandelion 

 (Taraxacum ojjicinale), to be met with in isolated examples flowering in spring, 

 summer, and autumn, the same thing may be observed. In May it opens between 

 7 and 8, at midsummer between 6 and 7, in August between 7 and 8, and in 

 September between 8 and 9 a.m. 



