342 Mr. Hassall on the Phosj)horescenc€ of Zoophytes. 



journal for June last, as detailing similar observations made 

 three mon ths before the reading of the paper. 

 The passage is the following : — 



"I have ascertained that all the more transparent Zoophytes," 

 (under which title I include the marine orders of the Hydroid, As- 

 teroid, and Ascidian classes, which embrace all the species indivi- 

 dually noticed by Air. Landsborough) " possess highly luminous pro- 

 perties. This fact I first discovered in a specimen of Laomedia gela- 

 tinosa, and subsequently in a great variety of other species. If a 

 portion of it, adhering to the sea-weed to which it is attached, be 

 taken from the water and agitated, a great number of bright phos- 

 l)horescent sparks will be emitted ; these sjDarks proceed from each of 

 the denticles of the coralline containing polypi, and the phsenomenon 

 is equally apparent whether the specimen be in or out of water. 

 The imagination could scarcely conceive a more beautiful spectacle 

 than would be furnished by the shining of countless myriads of these 

 tiny lamps, lighting up the dark recesses and caves of the ocean." 



" Tlie fact of the phosphorescence of one S2)ecies oi Sertularia, 



S. pumila, was, I have lately learned, discovered by Stewart some 

 time since ; but the announcement of it cUd not, it appears, lead to 

 further inquiries into this interesting subject." 



From a perusal of the above account^ to which I shall add 

 some additional observations, it is manifest that })riority of 

 upwards of a year, of the discoveiy of the general phospho- 

 rescence of Zoophytes, is due to me, and not to Mr. Lands- 

 borough. 



I have stated that the phosphorescence is equally apparent 

 whether the specimen be in or out of water, that is, in air or 

 water ; and this is the fact, the only requisite in either case for 

 its development being the friction of motion. 



Numerous friends, among others G. J. Allman, esq., of 

 Bandon, can bear witness to the exceeding brilliancy of the 

 phosphorescent light emitted by a great variety of species 

 which I Avas frequently in the habit of exhibiting to them. 

 Once each week I received from the master of a trawling ves- 

 sel on the Dublin coast, a large hamper of Zoophytes in a re- 

 cent state ; in the evening these were taken into a darkened 

 room, and the spectators assembled ; I then used to gather 

 up with my hands as much of the contents of the hamper as 

 I could manage, and tossing them about in all directions, 

 thousands of little stars shone out brightly from the obscu- 

 rity, exhibiting a spectacle, the beauty of which to be appre- 

 ciated must be seen, and one which it has been the lot of but 

 few persons as yet to have looked upon. Entangled among 

 the corallines were also numerous minute luminous Anne- 

 lides, which added their tiny fires to the general exhibition. 



Provided the Zoophytes had not been exposed to wet or 



