April 1, 1866.] 



SCIENCE-GOSSIP. 



77 



aerated by the action of the waves, the polyps of the 

 coral soon expanded. There most be some error in 

 this, for if two samples of water, one from the 

 inside and one from the outside of the harbours 

 were to be preserved at the same temperature and 

 examined a few minutes later, in vessels of the same 

 size and proportions, no difference that I can think 

 of could possibly be perceived in them as far as the 

 mere quantity present of free air is concerned. No 

 coral or sea anemone known to me is injured or 

 inconvenienced by any amount of aeration of the 

 water. They may, and do, certainly close tem- 

 porarily while the water is in the act of being 

 violently agitated, and it is possible that they may 

 be annoyed thereby, but as soon as the agitation is 

 over, they expand more than before, aud it is difficult 

 to conceive that Corallium rubrum — which, however, 

 I have never seen alive — should behave otherwise. 

 I quote from the "Natural History Review" 

 (Williams & Norgate) for July, 1865. 

 Jan. 20th, 1S66. W. Alfojsd Lloyd. 



P.S. — Feb. 1st. Since writing the foregoing I 

 have read in the " Auuals and Mag. Nat. Hist." for 

 September, 1858, a translation from the " Comptcs 

 Rendus " of the July preceding, containing an in- 

 teresting account of a large observatory for studying 

 living marine animals on the Quay of Concarneau, 

 in the Bay of Biscay, but as this arrangement (of 

 Professor Coste's) is in communication with the sea, 

 and the same water is not continually used, and as 

 no mention is made of vegetation, the establishment 

 cannot be termed an aquarium according to the 

 definition laid down. 



And when visiting Professor Coste's most in- 

 teresting fish-breeding place in the College de 

 Prance, in Paris, in 1S61, I observed with what 

 assiduity the assistaut scraped away the vegeta- 

 tion — conferva — which had formed on the cement- 

 ■covered sides of the reservoirs, as it was held to be 

 injurious to the fish (salmon and trout), and chiefly 

 to their eggs, by growing over them. Efforts to 

 eradicate it were all in vain, however, as it would 

 grow in spite of all scraping and scrubbing wherever 

 there was any light ; and if it were not present, the 

 fish would certainly not have presented so healthy an 

 appearance as they did, although copious streams of 

 water were provided in addition. W. A. L. 



DEATH-WATCH. 



"TN the February number of Science Gossip 

 -*- there appears an abstract of a paper read by 

 Mr. Smith before the Entomological Society, in 

 which he throws doubt upon the production of a 

 watch-ticking sound by the Atropos pulsatorius. 

 Inasmuch as I am, I believe, in a position to set this 



question at rest, I am induced to crave a little space 

 in your columns to relate the result of my expe- 

 rience. On the night of Sunday, the 23rd of last July, 

 I was sitting reading in my drawing-room, after the 

 rest of the family, and some visitors, had retired to 

 their rooms, when my attention was attracted by 

 what sounded like the loud ticking of a watch near 

 to me. My first impression was, that my own 

 watch, from some occult cause, was making much 

 more noise than usual ; but, on pulling it out, I at 

 once ascertained that it was not thence that the 

 sound proceeded. Ultimately, I traced it to the 

 mantel-piece, though scarcely (on this occasion) to 

 any specific part of it. So remarkable was the 

 imitation of the tick of a watch, so perfect the me- 

 tallic ring, and so utterly unlike any thing which 

 could conceivably be produced by an insect, that I 

 fetched down one lady, who had not commenced 

 undressing, to come and hear it. After this we used 

 to amuse ourselves every night by listening to the 

 ticking, until eventually, in October, I determined 

 to find out by what means it was produced. Upon 

 careful examination I traced it to one of the lustres, 

 which, by way of experiment, I removed to a distant 

 table. The first disturbance silenced- the insect, 

 but a few minutes' quiet reassured it, and on it went 

 again. Finally, I tracked it to a French paper 

 rose surrounding the base of the candle ; and upon 

 striking this sharply upon the table, there fell out a 

 specimen of the Atropos pulsatorius. This I exa- 

 mined under the microscope, and I must say that I 

 was quite as much astonished as Mr. Smith could 

 possibly be to see the extraordinary minuteness and 

 delicacy of the creature which had so perfectly 

 simulated the hard metallic ring of a chronometer 

 balance. Unfortunately, I squeezed my captive to 

 death in trying to confine him in a live-box, and so 

 put an end to him aud the ticking by one operation. 



After this, for a month or two, all was silent ; 

 when one night, towards the end of the year, while 

 sitting over the fire, my ears were saluted by the 

 well-remembered sound. Krperieutia docet: so I 

 straightway removed the lustre from the chimney- 

 piece, and, after listening to satisfy myself that I 

 had my friend safe, removed the rose from the base 

 of the candle, and, as before, by a sharp tap on the 

 table, knocked the Atropos out of it. I killed him, 

 or her, at once, intending to have mounted the 

 specimen as a microscopic object ; but, from 

 the extreme softness of the body it squeezed up 

 into an amorphous mass when I attempted to 

 flatten it. 



From that time up to the present date (Feb. 5) I 

 have heard no more "ticking," and so infer that I 

 must have destroyed a pair which had taken up their 

 abode in the candle ornament, and whose untimely 

 decease has cut off a possible generation of the 

 Atropos pulsatorius. 



William Noble, F.R.A.S., &c. 



