HARDVYICKE'S SCIENCE-GOSSIP. 



95 



mountain is almost flat on the top, and the sides are | 

 (in the neighbourhood of the boulders) remarkably j 

 steep and precipitous, and from the peculiar forma- 

 tion of the bed of boulders, and the marked absenoe 

 of any earth, gravel, or anything of a loose nature 

 in the neighbourhood, I am at a loss to account for 

 their formation, by the same process that produced 

 your correspondent's ; though, perhaps, if space 

 permitted, I may be enlightened. " Nearly 4,000 

 feet above the sea-level, and close to the summit of 

 the mountain, we come to what is called the Ploughed 

 ' Field, which is a collection of boulders filling an 

 immense natural basin or hollow, and altogether 

 covering several acres. Each boulder is of several 

 tons weight, the whole mass sloping upwards at a 

 steep angle. The bottom or lower end of the field 

 terminates abruptly in a precipice some hundreds 

 of feet deep. How deep the boulders lie, goodness 

 only knows ; but the interstices between them look 

 unutterably dark and dangerous, there being ample 

 room for several people to slip down at once, into 

 the black abyss below. We jumped, scrambled, 

 and climbed from boulder to boulder, as best we 

 could (taking good care not to slip), till safely 

 across, when we found ourselves within a few feet 

 of the flat summit of the mountain. One side of the 

 Ploughed Field is bounded by a wall of tall rocks, 

 in the shape of cylindrical pillars reared straight 

 upright, some of which are quite 50 feet in height, 

 and most of them are detached from those around, 

 so that the whole presents an appearance 



' Like a hu?e organ, formed by Nature's hand, 

 To thunder forth her great Creator's praise.' 



And so form a most imposing object." — IF. H. C. 



New Introductions. — I lately advocated in the 

 pages of Science-Gossip the introduction into 

 Great Britain of foreign ^ insects remarkable for 

 beauty or for peculiarity of structure, The follow- 

 ing passage from Mr. P. H. Gosse's well-known 

 " Introduction to Zoology " (vol. ii. p. 354) is so 

 much to the point, that I cannot resist transcribing 

 it. " We wonder that no one has tried to naturalize 

 some of those splendid foreign butterflies which 

 inhabit climates similar to our own, and whose 

 caterpillars feed on plants which grow naturally in 

 both localities ; and there are many such, especially 

 in North America; such as the beautiful Papilio 

 turtius and asterias, the former of which feeds in 

 the; larva state on the willow and ash, and the latter 

 on the parsnip and other umbellifersc. Both of 

 these are common, even so far north as Newfound- 

 land. It might, doubtless, be easily effected by 

 collecting the caterpillars in their own country, and 

 allowing them to go into chrysalis, in which state 

 they might be transported during the winter, and 

 be evolved here in spring. We have had a speci- 

 men of P. asterias produced here from a chrysalis 

 which we had brought from North America ; and 

 we have seen in the collection of Mr. Loddiges, a 

 specimen of Coronis, a noble Brazilian species, which 

 that gentleman informed us had been produced in 

 his conservatory at Hackney, having been probably 

 introduced in the earth of some imported plant. 

 We see no reason indeed why the magnificent Lepi- 

 doptera, even of the tropics, might not be reared in 

 our conservatories and stove-houses as readily as 

 the palms and Orchideseof the'same regions. What- 

 ever plant might be the food of the larva, it could 

 surely be obtained in England in the present state 

 of botanical science." We are scarcely, perhaps, 

 prepared to appreciate fully the latter part of this 

 sentence ; nor can we yet hope to see hothouses in 



which may be reared the insect gems of Brazil or 

 China, before whose glories the brightest flowers 

 must " pale their ineffectual fires." But I am still 

 of opinion, that, if the matter were taken up by a 

 few energetic minds, we might yet see the theory of 

 introduction converted into a reality, as there is no 

 reason whatever why the many beautiful insects of 

 North America and North Europe should not be 

 established in our islands. At any rate, it is no 

 slight encouragement to find the idea supported by 

 so mature and world-renowned a naturalist as Mr. 

 P. H. Gosse — IF. IF. Spicer, Potterne, Wilts. 



Cocoon of a hairy Caterpillar.— I imagine 

 that the species referred to by Mr. Murray (p. 63), 

 must be the well-known Tiger, Arctia caja. If so, 

 there is no question that the hairs are purposely 

 interwoven, as is, doubtless, also the case with 

 other species which introduce their own hairs into 

 the cocoon. Not all the species clothed with hairs 

 render them thus available, but those doing so, are 

 very careful, as may be noticed, so to commingle 

 them with the silk as to render the abode more 

 secure, and also the extremities of the hairs are 

 care.fullv placed, so as not to annoy the chrysalis. — 

 J. B. S. C. 



"Eye-stones." — This name has been applied, as 

 it appears, to several objects, similar in appearance, 

 differing greatly in size and structure. As long 

 back as 1763, Dr. Brookes described eye-stones, 

 which he puts apart from mineral objects, showing 

 eye-like markings, of the nature of agates or cor- 

 nelians. Some were found, he says, iu a quarry at 

 Shot-over Hill, which were oval and of a reddish 

 colour, containing a circle of white and a pupil, 

 having rather the appearance of an eye darkened by 

 a cataract. The size of these objects he does not 

 state ; it is probable that they were fossil shells. I 

 think that though some concretions found in the 

 heads of crustaceans may present this curious 

 resemblance to the eye, the case is exceptional, and 

 Mr. Izod is presumably right in assuming that his 

 eye-stones are shells. — J. jR. S. C. 



The Crab and its Claws. — Every one must 

 have observed that crabs have often one claw very 

 much smaller than the rest, and doubtless have in- 

 ferred that the crab has at some time or other 

 lost the original claw, and that the small one has 

 grown in the room of the missing member. This 

 inference is certainly correct ; but I fancy that very 

 few know when the new member first_ makes its ap- 

 pearance, but suppose, as I did, that it began as an 

 incipient claw, and gradually grew with its posses- 

 sor's growth. From the following circumstance, I 

 had an opportunity of knowing when a new claw 

 first makes its appearance. One of my crabs (I 

 believe from fighting, for they are very pugnacious) 

 had the misfortune to lose one of his forcep claws, 

 and thereby became greatly disabled from either 

 offence or defence. In this mutilated state he re- 

 mained for some time, taking, however, his food as 

 if nothing was the matter, but looking as all crabs 

 must look that have lost au efficient member. By- 

 and-by the time came when he must cast his shell, 

 and when he had accomplished this extraordinary 

 feat, instead of appearing with only one forcep claw, 

 he could now boast of two — one in the room of 

 the one he had lost. It certainly was considerably 

 less than the other, but still it was not an embryo, 

 but a good, substantial, well-formed claw.— A. L\ 

 Murray. 



