Mar. 1908.] | BOTANICAL SOCIETY OF EDINBURGH. 333 
MEETING OF THE SOCIETY, 
March 12, 1908. 
J. RurHerRFoRD Hi1, Esq., President, in the Chair. 
Mr. J. N. ZUTSHI was elected a Non-Resident Fellow. 
The following communication was read :— 
Luminosity In PLants. by Miss BERTHA CHANDLER, M.A. 
Communicated by Dr. A. W. BorTHWICK. 
The subject of luminosity in plants is an interesting one, 
from the very obscurity in which the subject is still wrapped. 
Comparatively speaking, not much research has been done 
in connection with the subject, and the cause and significance 
of this phenomenon in the majority of plants still remains a 
mystery. Investigations that have been carried out, however, 
have revealed much that is interesting. 
First of all considering the facts, and then the theories, 
we come first to the occurrence of this phenomenon in the 
higher plants. 
The so-called luminosity of the flowering plants does not 
really belong to this class of phenomena, but is possibly due 
to St. Elmo’s fire, a species of electrical phenomenon depend- 
ing on the condition of the atmosphere. but the cases 
observed were formerly explained as luminosity, and are 
interesting historically. The daughter of Linnzus is said 
to have been the first to remark the light issuing from a 
flowering plant. She noticed luminous radiations being 
emitted from a group of nasturtiums (Z7ropeolum majus). 
Other observers, too, have remarked the same phenomenon, 
and, curiously enough, almost without exception, in yellow, 
orange, and occasionally in red flowers, such for example as 
the sunflower (Helianthus)—garden marigold (Calendula)— 
two species of Yagetes, which the French call Rose d’Inde 
and (illet d’Inde. Dr. Phipson has called attention to this 
curious fact, that in almost all the cases noted of phosphor- 
escence, not only in the plant world, but even in the animal 
