PHANEROGAMIC PLANTS. 81 



to be connected in an extraordinary manner with 

 these phenomena. 



Seated one sultry summer evening in a garden, 

 the daughter of the illustrious naturalist observed 

 with surprise certain luminous radiations emitted 

 by the flowers of a group of nasturtiums. This 

 curious observation was made more than once 

 during twilight in the months of June and July, 

 1762. The girl lived long to tell her wonderful 

 tale.* 



The same phenomenon has been witnessed by 

 other naturalists, but almost exclusively on yellow 

 or orange-coloured flowers. Thus, it has been 

 seen, we are told, in the corolla of the sunflower 

 (Heliantlius annuus), in the garden marigolds 

 (Calendula), in the two species of Tagetes (which 

 the French botanists call the Rose d'Inde and the 

 (Eillet d'Inde). Phosphoric light has also been 

 seen to be emitted from the flowers of the Tu- 



* Mrs. Loudon, in her 'Ladies' Flower Garden,' p. 116, says: 

 " A curious discovery was made respecting this plant (Trop&olum 

 majus, L.) by one of the daughters of Linnseus, who died lately 

 at the advanced age of ninety-six. This lady, in the year 1762, 

 observed the T. majus, or garden Nasturtium, to emit sparks or 

 flashes in the morning before sunrise, during the months of June 

 and July, and also during twilight in the evening, but not after 

 total darkness came on. Similar flashes have been produced by 

 other flowers, and it has been observed that they are always most 

 brilliant before a thunderstorm." See also Paxton's Mag. of 

 Botany, vol. ii. p. 195. It has been asserted that certain flowers 

 always emit light at the periods of floration and fecundation. 



G 



