Experime7its on the Noctiluca miliaris. 403 



the number of the Elateridae, or fire-flies, possessing the same 

 faculty, amounts to at least thirty. Nor are these the only 

 families endowed with this singular power : it is exhibited like- 

 wise by the Scarabaeides, and is found also in the Paiims 

 sphcerocerus, the Scolopendra electrica^ and in several species 

 of the Fulgorae or lantern-flies. 'J'he ova also of some of these, 

 as in the Lampyris splendidula, are said to be luminous, and 

 the pupa and larva of this insect are reputed to possess the 

 same property, though in a less marked degree. It has been 

 stated also that the common centipede of this country has 

 been observed to be slightly luminous, and the same has been 

 afiirmed of the common earth worm ; but these statements 

 require further confirmation before they can be received with 

 confidence. 



Before quitting this division of our subject, it may be ob- 

 served that it is usual, in physiological writings, to find re- 

 ference made under the present head to the instances of lumi- 

 nosity in the living human subject which were brought under 

 the notice of the profession a few years since by Sir Henry 

 Marsh (Prov. Med. Journ. IS'l-S). The instances in question, 

 however, though highly interesting to the pathologist, like the 

 fact remarked by Cabanis of the excess of phosphorus in the 

 brain of maniacs, are nevertheless of a character which must 

 exclude them from our present inquiry. 



Passing then from the examples of phosphorescence thus 

 brought rapidly under view, as exhibited by that portion of 

 the animal creation confined to the land, we proceed briefly 

 to notice the instances of the same phaenomenon as displayed 

 amongst the tenants of the deep. And here, as led on in the 

 pursuit of this interesting subject to seek the ocean as the field 

 of his further research, the curious inquirer cannot fail to be 

 struck with the vastness and grandeur of the change presented 

 to his contemplation. Here he discovers not only a much 

 greater variety as regards the range and type of animal life 

 amongst which this power of phosphorescence is distributed, 

 but he will recognize some individual instances, which, though 

 so minute as to be revealed only by the aid of the microscope, 

 yet exist in such countless myriads, that the whole element 

 may be said to teem with them. 



In order to convey some idea of the general effect of the 

 phosphorescence of the ocean from the presence of a great 

 variety of luminous animals, and as witnessed on a large scale 

 at sea, I shall avail myself of some of the descriptions which 

 have been furnished us by travellers of accurate observation 

 and authenticity. In a highly interesting narrative of a 

 whaling voyage round the globe, from the year 1833 to 1836, 



2 D 2 



