110 On a new kind of Phosphorescence observed 



ophiuridas were in this condition, I have pricked them thoroughly, and 

 tortured them in all wajs, during which they remained quite motion- 

 less. If, after this, I, as it were, triturated one of their arms with a pin, 

 I obtained a little feeble light, but nothing more. Even organic con- 

 tractility appeared to become extinct in them, whilst in one of the genus 

 Syllis, we have previously seen how very long it continued. This mark- 

 ed difference appeared to depend upon the nature of the tissues, which 

 are much more solid in the Articulata, even those which are microscopic, 

 than in the Radiata. The orgapized layer which clothes the testa of 

 the ophiuridte, is very rapidly decomposed and dissolved ; and it cannot 

 long preserve those properties which appear to appertain exclusively to 

 the organization. 



These facts which I now publish, appear clearly to indicate a resem- 

 blance between the luminous phenomena of these minute animals and 

 the electrical phenomena which are possessed by the torpedo, gymnotus, 

 &c. In both of these classes, the imponderable fluid, light or electricity, 

 is wasted by an organized apparatus in a state of purity. In the fishes, as 

 in the annelides and ophiuridse, this fluid is smartly disengaged by dis- 

 charges : these discharges, electrical or luminous, progressively diminish 

 in intensity ; they speedily fatigue the animal submitted to the experi- 

 ment, and a longer or shorter repose is necessary ere the phenomena can 

 again be produced. 



M. de Humboldt has kindly communicated to me certain unpublished 

 observations made by M. Ehrenberg, and which corroborate those above 

 detailed. The illustrious microscopist of Berlin has observed among 

 some small marine animals approximating to the Noctiluques a special 

 luminous organ which he compares to the apparatus of the electrical 

 fishes. He has also been led to admit that in this organ there is the ap- 

 pearance of light by sjparks.. and by a discharge, and independent of all 

 material secretion. In short, he has, as I have done, assimilated the 

 production of light in these microscopic beings, to the production of 

 electricity in fishes. 



There is, however, a fundamental difference between the facts I have de- 

 tailed, and those observed by M. Ehrenberg. In the annelides and ophiuridse 

 no special luminous organ is to be found ; and the function is devolved 

 upon the muscles. This last particular, however, is not of a nature to 

 prejudice the minds of naturalists, since the beautiful experiments of M. 

 Matteucci have, in the higher animals, demonstrated that the existence 

 of electric currents are manifestly apparent in the muscular masses. 

 Natural philosophers are coming every day to consider the different im- 

 ponderable fluids as being only simple modifications of one and the same 

 agent ; and it is no difficult matter to conceive that this agent, when put 

 in motion in living bodies, and particularly in the muscles, may exhibit 

 itself sometimes in the form of light, and at other times under that of 

 electricity. 



I shall conclude this notice with this single reflection. It is well known 



