476 Qiteries and A?iswers. 



sure, and no doubt, by trimming it to the wind, make it act the part of a 

 sail to propel themselves through the water. " They are very often to be 

 met with at sea," says Sir Hans Sloane ; " and seamen do affirm that they 

 have very great skill in sailing, managing their bladder or sail* with judg- 

 ment for this purpose, according to the different winds and courses." 

 (Sloane^s Voyage to Jamaictty vol. i. p. 7.) Upon attentively examining the 

 narrow or free extremity of the bladder, a small round aperture is percep- 

 tible, surrounded by a circular zone of fibres, of a beautiful red colour, like 

 the muscular fibres of the iris of the eye. Out of this small hole, which is 

 not larger than would be sufficient to admit the passage of a very fine 

 bristle, I squeezed the air out of the bladder. It is by this aperture (which, 

 by the by, I have never seen described) that the animal, I presume, expels 

 the air from the bladder, when he wishes to sink under the surface of the 

 water ; but whether he refills it, by inhaling the air by this aperture, or 

 secretes it from his blood, I shall not undertake to determine. They pos- 

 sess in a high degree the stinging quality which has procured for the 

 animals belonging to the Radiata the term sea nettles. They are also 

 endowed with the luminous property which belongs to so many marine 

 animals ; and I have never failed to observe, when they have been nume- 

 rous during the day, that the sea at night has been brilliantly illuminated. 

 Sir Hans Sloane, in his Voyage to Jamaica, has given a figure of this inter- 

 esting little animal, plate 4. fig. 5. " i/rtica marina soluta, purpurea, 

 oblonga, cirrhis longissimis — a caravell." The plate, however, is exceed- 

 ingly bad ; the crust is much too large, and altogether, as Lamarck observes, 

 it is " tres-mauvaise." — W. Baird. 8. Everett Street, Russell Square, 

 Apnl 10. 1831. 



E^ later murinus, with a branched Antenna. — Sir, I captured some time 

 since, on a nettle in the Battersea Fields, a specimen of E'later murinus, re- 

 markable for an extraordinary appendage attached to the second joint of 

 the left antenna. This appendage consists of two antennae, if I may so 

 call them, each composed of nine joints, very stout. The natural limb 

 however, though containing its usual number of eleven joints, is weak and 

 slender, and not above half the length of the right antenna, which is per- 

 fect, and has no appendage attached to it. I should feel obliged if any of 

 your readers could inform me if such instances as the present are of frequent 

 occurrence, and to what cause, sexual or otherwise, this singular formation 

 of the antennae may be attributed. I am. Sir, yours, &c. — A Lover of the 

 Science. July 14. 1831. 



The supernumerary appendage found on the tarsus of Chlanius vestitus, 

 as figured and described in Vol. II. p. 302. fig. 86., may be cited as a case 

 remotely parallel to the above. — J.D. 



The Water Beetle. (Vol. III. p. 148.) — I should be obliged if you, or any 

 of your correspondents, would inform me what species of insect is meant 

 by " the water beetle," and to what previous communication the notice 

 there refers. The destructive propensity of the insect in question renders 

 it a matter of importance that its species should be accurately ascertained. 

 — B. Coventry, April, \mQ. 



Queries by Agronome. — Sir, I shall endeavour, in this letter, not to offend 

 any of your readers, by rambling out of my element, and getting among the 

 Stars or comets, but content myself with asking a few questions respecting 

 the lower order of creation. And first, you have not satisfied me what are 

 the origin and end of the hairworms (Gordius and Filaria, Vol. I. p. 301., 

 II. p. 103. 211., III. p. 149. fig.32. p. 459. fig. 1 14.). I dare saythat you, like 

 me, when a boy, have been told that it was a horse-hair dropt in the water, 

 and that the moisture swelled it into life ; we have also heard of a lady 

 who oiled her hair to such a degree, that each hair swelled into a serpent, 

 and stung her to death. When a cowboy, I often tried to bring hairs into 

 life by steeping them in water, but without effect. I then concluded that 

 the hairworms were young eels, and kept some in bottle?, but still they 



