HARDWICKE'S SCIENCE-GOSSIP. 



263 



never parted company with the limpet. There exists 

 between the shell and the living tissue an extremely 

 intimate union brought about slowly iu the progress 

 of the growth of the animal. But perhaps owing to 

 the formation of some cement substances, a rapid 

 temporary union may possibly be formed between the 

 rock and the living tissue of the limpet. With 

 regard to the secretions of the limpet, it may be 

 mentioned that many species gradually eat their way 

 into the hard strata to which they may be attached — 

 limestone, old red sandstone, &c. It is evident 

 that the limpet is a distinguished independent 

 practical manufacturing chemist, whose small self- 

 contained domestic portable laboratory makes three 

 home-made special and distinct natural secretions. 

 One to build its shell, the other to glue itself to its 

 native rocks, and the third secretion to act as a 

 solvent to partially dissolve certain geological soils. 



The Variegated Slug. — I have sent you a slug 

 by parcel post, which I believe to be the variegated 

 slug {Limax variegatus). You will doubtless recog- 

 nise him. I have a natural bed of mushrooms, which 

 these slugs attack directly they come above the 

 ground, and consume them. I enclose you some of 

 the partially eaten mushrooms, with a fine specimen 

 of the slug. I can send you some more of them ; I 

 expect some of you have a mushroom-bed to feed 

 them on. Can any reader tell me how I can get rid 

 of the voracious slugs without destroying my natural 

 bed, which is on a gravelly earth-made soil close to 

 the salt water, but elevated, a quay in fact, so that 

 the salt water does not flow over it. — W. Penney. 



Intelligence of Monkeys. — Some time ago, I 

 saw in a magazine, a statement to the effect that no 

 monkey possesses sufficient intelligence to untie a 

 knot ; this of course is erroneous, as probably every- 

 body who has kept a monkey knows. Mr. Belt in 

 "The Naturalist in Nicaragua," says, that his 

 monkey not only untied knots, but opened the links 

 of a chain. At the same time, the statement that 

 they cannot, must I presume, have been founded on 

 some evidence, and, as some observations which I 

 made bear on this subject, they may not be entirely 

 devoid of interest. In 1884 I was in camp in 

 Gorakhpur ; I was one day given a young monkey 

 just caught ; as was my usual practice with wild 

 animals I kept it tied up for a couple of days, feeding 

 it well and frequently stroking it, and then gave it 

 entire liberty. Unlike the other animals, however, 

 the monkey did not avail himself of his liberty to go 

 away temporarily ; on the contrary, he seemed afraid 

 to venture to any distance from my tent, and the 

 sight of wild members of his own species threw him 

 into a condition of abject terror. He soon became 

 very tame, and very inquisitive, but contrary to my 

 expectations, not mischievous ; on the contrary, he 

 was almost ludicrously careful not to injure anything, 

 and when he accidentally broke any article, he 

 seemed much distressed. I had business at a place 

 named Chaumukha, where there was a bungalow in 

 which I stayed, and here the monkey became a 

 nuisance, jumping into my lap, and wanting to be 

 nursed, when I was writing ; accordingly I tied him 

 to the leg of my bed with a piece of thin rope. For 

 one day this was effectual, but the second day, soon 

 after I had begun writing, the monkey made his 

 appearance, trailing the rope, having evidently untied 

 it from the bed-leg. The next day I tied him up as 

 before, but instead of going away, I hid behind the 

 door and watched. The monkey first examined the 

 knot very carefully, turning it over with his hands, 

 and apparently tracing the course of the rope with 



his fingers, but making no attempt to untie it ; after 

 he had studied it for some time, he untied it without 

 any hesitation and fairly rapidly ; I noticed that he 

 only used his fingers, and that they seemed to be 

 somewhat clumsy. This suggested to me that if I 

 used thinner cord, the monkey might be unable to 

 get a grip with his fingers, and on trial I found this 

 was so ; moreover, the monkey, after having vainly 

 tried to untie the knots for a couple of hours, gave it 

 up in despair, and then made no further attempt on 

 any subsequent day. So, if I had then given the 

 monkey to someone else, and he had tied it up with 

 thin cord, he might have concluded, from the fact of 

 the monkey making no effort to untie the knot, that 

 he lacked the necessary intelligence, while it really 

 resulted from his knowledge of the uselessness of the 

 attempt.— 7. R. Holt. 



What length of three-quarter-inch diameter pipe 

 would be required to .hold exactly one gallon of 

 water ? An answer in Science-Gossip to this 

 question will greatly oblige an old and regular sub- 

 scriber. — R. C. Chaytor, Sera/ton Lodge, Middle/iam. 



NOTICES TO CORRESPONDENTS. 



To Correspondents and Exchangers. — As we now 

 publish Science-Gossip earlier than formerly, we cannot un- 

 dertake to insert in the following number any communications 

 which reach us later than the 8th of the previous month. 



To Anonymous Querists. — We must adhere to our rule of 

 not noticing queries which do not bear the writers' names. 



To Dealers and Others. — We are always glad to treat 

 dealers in natural history objects on the same fair and general 

 ground as amateurs, in so far as the "exchanges" offered are 

 fair exchanges. But it is evident that, when their offers are 

 simply Disguised Advertisements,^ the purpose of evading 

 the cost of advertising, an advantage is taken of our gratuitous 

 insertion of "exchanges," which cannot be tolerated. 



We request that all exchanges may be signed with name (or 

 initials) and full address at the end. 



Special Note. — There is a tendency on the part of some 

 exchangers to send more than one per month. We only allow 

 this in the case of writers of papers. 



To our Recent Exchangers.— We are willing to be helpful 

 to our genuine naturalists, but we cannot further allow dis- 

 guised Exchanges like those which frequently come to us 

 to appear unless as advertisements. 



Correspondent, c.o. Mrs. Grimes, Coningsby House, 

 Staines. — The Editor is sorry to be obliged to address you as 

 above, but your note had no personal address. The specimens 

 forwarded are extremely interesting. The plant is the yellow 

 cornflower {Ckrysosfilenium segetum). The "monstrosity" 

 seems to be due to the hyper-development of the receptacle, 

 this being a composite plant. As far as could be made out the 

 "monstrosity" is due to the action of some species of gall 

 insect. 



Llesba. — The stone you refer to is evidently a lower chalk 

 flint containing the impression of the spine of a fossil Cida-ris, 

 or sea-urchin. See Taylor's "Common British Fossils" (Lon- 

 don: Chatto & Windus). 



C. W. Maw. — It was very difficult to correctly identify your 

 larva, but it seems to be that of the common swift (//". lufac- 

 lind), 



C- W. Oakden. — We shall be very pleased to have short 

 reports of the meetings of the Q.M.C. at any time, for 

 publication in Science-Gossip. 



W. Groves. — Many thanks for the double apple. We pub- 

 lished the illustration of a similar one in 18.70, in the papers on 

 "Vegetable Teratology." It is also illustrated in Dr. Master's 

 famous book on the same subject. Double apples and plums 

 are not uncommon, as every fruiterer on a large scale will 

 inform you. 



I. W. Measures. — See Dr. Aitkin's papers read before the 

 Royal and Physical Societies of Edinburgh, on "Dust." 

 Most of them were lengthily reported in "Nature," to the 

 editor of which please apply. 



J. Klonowsky. — The occurrence of three-clawed lobsters 

 and crabs (in front claw) is not uncommon. 



