198 On the Phosphorescence of Marine Invertebrata. 
chemical actions which take place in our laboratories, but without 
explaining himself very fully on this subject. This naturalist 
regards phosphorescence as due to Crustacea belonging to dif- 
ferent genera; he allows that the seat of this light, emitted on 
irritation or at the time of procreation, resides in glands placed 
in a variable number on the sides of the thorax. He adds: “this 
light should be regarded, as a fact established by investigation, as 
a modification of the laws of life, and as different from the sim- 
ple sparkling light resulting from the decomposition of animal 
substances.* eek 
Carus, losing sight of the philosophy which prevails in his 
works, adopts the opinion that this phenomenon is a property of 
primary animal matier, which is nothing else than the nervous 
substance and which representing the solar element in the animal 
necessarily appears luminous to the planetary element.+ He then, 
as well as Oken, from whom he cites the passage, “regards the 
jelly of Zoophytes, Medusz, &c., as the nervous substance 1n us 
lowest stage, from which the other substances embraced within 
it have not been isolated.” . 
M. Bérard, cited by Duges,{ regards the phosphorescence of 
animals as due to a kind of luminous imbibition, or purely vilal 
effect, analogous to those which result in different bodies, from 
the action of heat, electricity, light, &e. : 
Dr. Coldstream published in Todd’s Encyclopedia a very intel 
esting article on phosphorescence.§ After having examined 
nature of animal light, the natural or artificial circumstances 
which influence its appearance or intensity, the points of body ™ 
different animals from which it is produced, he sums up all that 
we have learned from different authors of the phosphorescent 
organs, and the different theories proposed to explain these ph 
e quote from this English author some passages from 
this part of his work. 
According to Becearia, Meyen, &c., the phosphorescence of alr 
imals is owing to what they absorb from the rays of the sum 
which they throw out again in the dark. ie 
Spallanzani regards phosphorescence as a kind of combustioP 
sustained by the oxygen of the air. i food 
_ According to Brugnatelli, the light is taken in with the 1% 
and disengaged by particular organs. of 
ire considers the phosphorescent matter as composed 
phosphorus and albumen. The variations of intensity nantes 
in the light arise more or less from the coagulation of the 
Se. Natur., 1826, article Phosphorescence. 
* Dict. des 
} Traité élémentaire d’anatomie comparée, traduit par Jourdan, t. iL 
Traité de physiologie compar rina e > 
ame yelopedia of anatomy and physiology, Part xxii, article Animal lomino® 
