THE MAGAZINE 



OF 



NATURAL HISTORY 



MAY, 18^9. 



Art. I. On certain Effects produced by Fresh Water on some 

 Marine Animals and Plants, Read to the Belfast Natural 

 History Society, by the President, James L. Drummond, M.D., 

 December 30. 1828. 



During the past summer, a part of which I spent at the sea- 

 side, I was anxious to confirm, beyond a possibility of doubt, 

 an observation which I had made several years ago, viz. that 

 when the Squamous Sea Mouse (Aphrodit^^ squamata) is put 

 into fresh water it dies almost instantaneously. I could not, 

 however, obtain any specimens, but I am certain, at the same 

 time, that it is a fact ; for, on a former occasion, I brought from 

 the shore seven or eight specimens of that animal alive in a 

 phial of sea water, and I found in them all, that, although 

 perfectly brisk and active in the sea water, the moment they 

 were dropped into a basin o^ fresh water (and I made the 

 trial on them one after another), they immediately sank to the 

 bottom, and never again exhibited the slightest symptom of 

 life or motion. 



The observations I have made lately on another species of 

 animal, of much larger dimensions, are not a little singular, 

 and are, I apprehend, altogether new. I obtained a number 

 of living specimens of the worm, which the fishermen call the 

 White-worm, or Lurg, or Lurgan. It is the Nereis caerulea 

 of Linnaeus. These specimens were quite fresh, and were 

 brought to me in a bowl of sea water. When handled, they 

 moved with great vivacity, convoluting or twisting their bodies 

 from side to side, like the larva of a gnat, or else swimming 

 with great velocity round the basin. They were about as 

 thick as one's little finger, and fully a foot in length. 



On putting one of them into a basin containing some fresh 

 water it sank to the bottom, and lay for a moment motionless, 

 as if stunned. It then dashed here and there through the water, 



VoL.II. — No. 7. K 



