Qjicrics and Ansivrrs. ' ^05 



cliinks in the bark arc themselves deep in the acacia, perhaps more so than 

 in most trees. Both grooves anil chinks,however, the creeper can well enough 

 explore by virtue of the length of its bill (in Montagu's Dictionary^ " half 

 an inch ; " is it not slightly longer ?) ; and the elegant attenuation of its 

 mandibles, and the acute points in which they terminate, enable it easily to 

 take the smallest insects. An adaptation of structure to function is herein 

 perceptible; and, if I rightly remember, Mr, Yarrcll has told me that the 

 breast-bone of this bird has little or no keel, to the end that its climbing 

 habits may not receive the impediment which a prominent keel would occa- 

 sion. — J.D. 



Oniithoscope (p. 83.). — Is this a newly invented instrument, possessing 

 peculiar optical powers; or is it but a new name for the common telescope, 

 expressive of the ornithic scope to which the telescope is applied ? — D. S. 

 Jan. 26. 1832. 



7^/ie rolyomwaliis Argiohis {Azure-hhe BiiUerfly^ is doiiblc-hrooded . — 

 Sir, Mr. Brce asks (Vol. IV. p. 477.) if this is a double-brooded insect; 

 and Mr. Jordan answers (Vol. V. p. 109.) in the affirmative. 1 think he is 

 right. I have seen, both in the spring and autumn, what I consider the 

 same species ; and should I have an opportunity of observing it this year, 

 I will preserve some specimens at both seasons. About five miles east of 

 Cambridge, in a low meadow of coarse grass, adjoining a shrubbery, and 

 bordered by a rivulet, I saw this butterfly, about the end of August, 1830, 

 in great numbers. In the spring of 1831, I saw it in the same situation, 

 though much less numerous ; but in the autumn of that year, I passed seve- 

 ral times without seeing a single specimen; and I conclude I was either too 

 early or too late for it. Mr. Bree speaks of the caterpillar feeding upon 

 holly and ivy; but there was, I believe, neither of those trees in the neigh- 

 bourhood where I saw the butterfly. I'he Butterfly Collector's Fade Meciini 

 says it feeds on grass ; and from the situation in which I saw it, 1 am 

 inclined to think that statement correct. I am, Sir, yours, &c. — E. Ven- 

 tris. Cambridge, Ja7i. 25.1832. 



Humming in the Air, — Sir, The humming spoken of by your correspond- 

 ent O. (Vol. V. p. 110.), I have no doubt, proceeded from the common 

 gnat (C'ldex pipiens). I have frequently heard (at first with surprise) the 

 noise he speaks of, when the authors of it have been invisible. At other 

 times I have heard exactly the same sound ; and looking upwards for some 

 time, I have just been able to see the van of an army of gnats. The super- 

 natural music in the air, described by superstitious villagers, must be attri- 

 buted to the same cause. Kirby and Spence (/n/rorf. to Entom., vol. ii. 

 p. 377. 1st ed.), alluding to the passage in White's Natural History of Sel- 

 borne, remark: — " The hotter the weather, the higher insects will soar; 

 and it is not improbable that the sound produced by numbers may be heard 

 when tho.se that produced it are out of sight." The gnat has long been 

 celebrated as a trumpeter. Homer, in his Batrachomyomachia [Battles of 

 the Frogs] says : — 



Koi rorf KwvojTreg /.isyaXag (raXTnyyag t^oj-Tfr, 

 Amur taa\TTiZ,ov TtoXkjxov ktvtvcv. 



" Huge * gnats. 



Through clarions of unwieldy length, sang forth 

 The dreadful note of onset fisrce." Coicpcr. 



And Spenser, in his Faery Qncene (b. ii. c. ix. IG.), says : — 



* The epithet huge is a volunteer of the translator's; and fnycWai rraX- 

 TTiyytc is used from the great sound, rather tluui the unwieldy length, of 

 their instruments. 



