PHANEROGAMIC PLANTS. 83 
quently seen on the same flower two or three 
times in quick succession, but more commonly at 
intervals of several minutes; and when several 
flowers in the same place emitted their light to- 
gether, it could be seen at a considerable dis- 
tance. This phenomenon was remarked in July 
and August at sunset, and for half an hour, when 
the atmosphere was clear; but after a rainy day, 
or when the air was loaded with vapours, nothing 
of itwas seen. ‘The fact of this phenomenon only 
occurring when the air is dry, leads us naturally 
to presume that it is connected with electricity. 
The following flowers were observed by M. Hag- 
gern, to emit flashes more or less vivid, in this 
order: 1. The marigold (Calendula officinalis, 
fig. 7). 2. Monkshood, or garden nasturtium (T'ro- 
peolum majus). 3. The orange lily (Liliwm bulbi- 
ferum, fig. 8). 4. The French and African mari- 
golds (Tagetes patula and T’. erecta). 
To discover whether some little insects or 
phosphoric worms might not be the cause of this 
emission of light, M. Haggern carefully examined 
the flowers with the microscope, but no animal 
organisms were found. The rapidity of the flash 
seems to indicate that electricity has something to 
do with the phenomenon. The same philosopher, 
after having observed the flash from the orange 
lily, the anthers of which are a considerable dis- 
tance from the petals, assured himself that the 
