248 VIEWS, &C. PHYSIOGNOMY OF PLANTS. 



whole cirrus; until the living flame runs also over tho 

 back of this nereid-like animalcule, making it appear under 

 the microscope like a burning thread of sulphur with a 

 greenish-yellow light. In the Oceania ( Thaumanthias) hemi- 

 sphcerica, the number and position of the sparks correspond 

 accurately, at the thickened base, with the larger cirri or 

 organs which alternate with them, a circumstance that merits 

 special attention. The manifestation of this wreath of fire is 

 an act of vitality, and the whole development of light an organic 

 vital process, which exhibits itself in Infusorial animals as a 

 momentary spark of light, and is repeated after short intervals 

 of rest."* 



The luminous animals of the ocean appear, from these con- 

 jectures, to prove the existence of a magneto-electric light- 

 generating vital process in other classes of animals besides 

 fishes, insects, mollusca, and acalephse. Is the secretion of 

 the luminous fluid which is effused in some animalcules, 

 and which continues to shine for a long period without 

 further influence of the living organism (as, for instance, in Lam- 

 pyrides and Elaterides, in the German and Italian glow-worms, 

 and in the South American Cucuyo of the sugar-cane), merely 

 the consequence of the first electric discharge, or is it simply 

 dependent on chemical composition? The luminosity of insects 

 surrounded by air assuredly depends on physiological causes 

 different from those which give rise to a luminous condition 

 in aquatic animals, fishes, Medusae, and Infusoria. The small 

 Infusoria of the ocean, being surrounded by strata of salt- 

 water which constitutes a powerful conducting medium, must 

 be capable of an enormous electric tension of their flashing 

 organs to enable them to shine so vividly in the water. They 

 strike like the Torpedo, the Gymnotus, and the Electric Silurus 

 of the Nile, through the stratum of water: whilst electric 

 fishes which, in connection with the galvanic circuit, are 

 capable of decomposing water, and of imparting magnetic 

 power to steel needles, (as I showed more than half a century 

 ago,f and as John Davy has more recently confirmed,!) yield 



* Ehrenberg, Ueber das Leuchten des Meeres, 1836, s. 110, 158, 160, 

 163. 



f Versuche uber die gereizte Muslcel- und Nervenfaser, bd. i. s. 438 

 441; see also Obs. de Zoologie et d'Anatomie comparee, vol. i. p. 84. 



J Philosophical Transactions for the year 1834, part ii. pp. 545 

 $47. 



