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IV. On the Danger of Hasty Generalization in Geology.
By ALEXANDER BRYSON, Esq.

After deducing examples of hasty generalization, and showing the frequency of erroneous conclusions drawn from scanty data, he gave the following example, of which he was himself guilty: In the summer of 1856, a few friends joined me in a yachting expedition, to geologise among the islands of the Firth. Among other islands we visited Inch Mickery, and spent some hours in examining its structure. On the southern summit of the rock, a quantity of lead was found, filling up many of the interstices of the trap, which had, besides, a very scorched appearance. This circumstance naturally excited our curiosity, and many theories were formed to unriddle the enigma, but in vain. We carefully examined the island, but could not find a trace of a fire by which the lead could have been melted, except at such a distance from the rock as to render the idea of lead being carried so far without cooling inadmissible. Then the lead had run into the crevices of the rock, showing that it must have been very fluid when it fell. The absence of every trace of carbon around the lead, or at all near the rock itself, was very puzzling. About this time our talented member, Dr Heddle, had announced the occurrence of native lead embedded in meteoric iron, and I at once held my Inch Mickery lead as truly meteoric in its origin. This idea was rendered the more probable, as Dr George Wilson, who kindly analysed it, failed to detect in it any trace of silver. Professor Fleming, although he scouted the notion of its meteoric origin, kindly accompanied us on a second visit to the island. After a personal examination, he was unable to throw any light on the

subject, but advised us to wait patiently, and time might clear up the mystery. We would have rejoiced had he lived to learn the simple explanation only obtained a few months ago. The Board of Fisheries some years since took it into their heads that garvies were young herrings, and passed an act forbidding nets to be used the meshes of which were smaller than those employed in catching full-grown herrings. The officers of the Board happening to detect a boat using the illicit nets just off Inch Mickery, they, according to statute, took the offending nets to this rocky knoll and burned them. The leaden sinkers attached to the nets supplied my meteoric lead, and the twine yielded sufficient fuel to fuse it.

V. Notes on some points in the Natural History of the West Coast of Ross-shire. By JOHN ALEX. STEWART, Esq., Lochcarron.

The first part of this paper was occupied with an inquiry into the food and some points of the natural history of the limpet. Besides the common species, Patella vulgata, Mr Stewart had detected the finer species, P. athletica (which had hitherto been chiefly found in the southern coasts of Britain), in great abundance upon the coasts of Ross-shire and Skye. He satisfactorily proved that the food of the common limpet was not confined to sea-weeds, as was generally supposed, but that it also fed upon Balani; and that the chief food of the P. athletica was the Corallina officinalis. Wherever that plant was in abundance, there Athletica was to be found; and it was not confined to the low-water zone, as it is said to be in the south of England. Mr Stewart described the process of feeding on the Balani and Corallina, and exhibited specimens of the half-digested remains taken from their stomachs. Mr Stewart also exhibited and described a species of Comatula, which he considered different from the common C. rosacea. He had, however, been anticipated in this discovery, Mr Barrett having published this species in the “Annals of Natural History," in 1857, under the name of Commatula Woodwardii. Mr Stewart farther exhibited a magnificent Ophiura, new to Britain, which he had discovered in the same locality. It was 24 inches across, and differed materially from any even of the genera of this family hitherto found

in our seas. It belonged to the genus Asteronyx, described by Muller and Troschell in their work on star-fishes. It seemed doubtful whether it was the same species which they had described under the name of A. Lovenii from Norway. In the main, it very closely corresponded with their description, but there were one or two discrepancies, which might either be specific, or variations dependent upon the age of the animal. Mr Stewart had only found one specimen; therefore, in the meantime, he was not in a condition to give an opinion upon this point. Mr Stewart, in conclusion, gave some interesting notices regarding the pulsation of the snail as compared with that of other animals; and also some notices of peculiar geological features which he had observed in Ross-shire.

VI. A beautiful Series of Varieties (in plumage) of the common Pheasant, were exhibited, the property of Walter May, Esq. By ANDREW MURRAY, Esq.

Wednesday, March 23, 1859.-WILLIAM RHIND, Esq., President, in the Chair.

JOHN S. LIVINGSTON, Esq., Leith, was elected a Member of the Society.

The following Communications were read :

I. Extract of Letter from the Rev. Hugh Goldie, Old Calabar, to Dr Greville, respecting some singular Silk " Bags" formed by Insects in Africa. Communicated by W. H. Lowe, M.D.

The following extract of the letter was read by Dr Lowe, and specimens of the very curious "Bags" therein described were exhibited :—

"Last year a brother of King Eeyo undertook a trading expedition to Efeet. [This is a country lying on the side of the Camaroons Mountain, nearest the Old Calabar River.] In the smaller box you will find something which he brought to me as a curiosity, it being quite unknown in Calabar. The articles are small bags, woven by what would appear to be an insect of the same family as the silkworm. The insects are said to form these on trees, many working at one bag; and, having completed their task, each one rolls himself up in his

own shroud and dies. The people of Efeet sometimes take a number of insects and put them in one of their native pots, when they commence to work, and line the interior of the pot with their bag, by which means the people obtain large ones, which they use to put cloth in, or any light article, and which are said to be waterproof."

Dr Lowe regretted that, while the objects were of themselves of the highest interest, he was able to offer so little in the way of information respecting them. There was no doubt, however, that they were the production of lepidopterous insects, and this belief was confirmed by Mr Andrew Murray, who brought to the Society an excellent drawing of some bags extremely analogous to those exhibited, and which are known to be the production of a gregarious butterfly in Mexico, a description of which, together with an illustrative plate, will be found in the Transactions of the Entomological Society of London, vol. i. p. 38, published in 1836. As one of the bags from Africa was much more dense in its texture than the others, Dr Lowe was led to think that two species of insect had been employed; but Mr Logan thought both might be produced by the same butterfly or moth. Mr J. T. Syme added some remarks; and all the members joined in the hope that specimens of the insect, in any state of transformation, or however roughly preserved, might at a future time be procured by the kind agency of Mr Goldie.

II. A Series of recently-discovered Eyeless Beetles from the Caves of Carniola and Hungary were exhibited-By ANDREW MURRAY, Esq. Mr Murray exhibited a fine series of eyeless beetles from the various caverns, &c. where these curious and rare animals have been found. There were twenty-six different species shown, of which there were a number which had been only discovered and described within the last two years, the possession of which he owed to his friend Herr Dohrn of Stettin. He pointed to the two new genera-Pholeuon and Drimeotus -as being of special interest, as filling up a blank between the genera of Leptoderus and Adelops, and proving that the former of these genera truly belonged to the family of the Cholevidæ, instead of being allied to the genus Mastigus, as

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