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ZOOLOGY. The Posterior Lobes of the Brain in the Lower Animals.—The controversy raised by the statement of Professor Owen, that the posterior, or third, lobe of the cerebrum (brain proper), is peculiar and common to the genus homo, and that certain parts found in the hind lobe are equally restricted to man, still attracts the attention of physiologists and comparative anatomists. Dr. Turner, Demonstrator of Anatomy at Edinburgh, agrees with the oppo nents of Professor Owen, that it is now fully proven that the Quadrumana (monkeys) possess a posterior lobe, with its characteristic parts. He has also found very decided posterior lobes in the cerebrum of certain Cetacea (whales), as well as a high degree of complexity in the convolutions of the brain.
In-and-in Breeding of Domestic Animals. It is a generally received opinion that in-and-in breeding, while it is extremely injurious in the case of the genus homo, is not accompanied by similar evils among domestic animals. A contributor to the Comptes rendus speaks thus forcibly upon this subject :-" Breeding in-and-in is, under no circumstances (as has been advanced by a forced interpretation of what passes in domestic animals), a practice favourable in itself, and altogether without danger. Far from it, it is for all species a cause of degeneration and decay. It is useful sometimes to have recourse to it as a necessary evil, to which one must submit in order to reap a counterbalancing advantage ; but the practice should be discontinued as soon as there is no longer an absolute necessity for it."
The Unicorn.- Dr. Baikie, the African traveller, announces that he is upon the track of this, as hitherto supposed, fabulous animal. Writing from Central Africa, he says that several years ago he heard allusions to such an animal, as he ascended the Niger, which were so circumstantial that his scepticism was shaken, and, at all events, he is disposed to hold that its nonexistence is not proven. Two informants told him they had seen the bones of such an animal, particularly describing the long straight (or nearly straight) black horn. He states that the hunters are well acquainted with the onehorned rhinoceros, and carefully distinguish between it and the presumed unicorn. No doubt the vast forests and unexplored wastes of Central Africa contain many unknown animals, and Dr. Baikie gives a list of native names by which this strange creature is called in various African dialects.
The Aye-aye. The most remarkable addition made of late to the stock of living animals at the Zoological Society's gardens is an Aye-aye (Cheiromys Madagascariensis). This extremely rare and curious nocturnal animal has only comparatively recently been known even to the natives of the islands which it inhabits. Mr. Edward Mellish, of the Mauritius, going on a mission of congratulation to King Radama II., on his ascent of the throne of Madagascar, took such effectual steps, that, although he could not at that time procure a specimen, one shortly afterwards was forwarded to him, which has reached London alive and in good health.
Sounds produced by Mollusca.—The lakes of Ceylon contain shell-fish which, Sir E. Tennent informs us, produce remarkable sounds, referred by the Cin
ghalese to species of the genera Littorina and Cerithium. Similar sounds have been observed in South America ; and a recent observer in the North, about Vancouver's Island, has discovered the existence of a similar musical mollusk in an arm of the sea running out of Victoria harbour. The sound was compared to that of a Chinese kite when flying, and which is produced by fixing pieces of metal to the kite's tail. The Indians were well acquainted with the sound, and referred it, like the Cinghalese, to a shell-fish, but the observer had not hitherto been able to obtain specimens.
The Young Fry of Anodonta Cygnea.--A remarkable fact in the history of this fresh-water mussel has been brought to light, viz., that the young fry are parasitic upon fishes. At the time of the exclusion from the ovum, says the Rev. W. Houghton, they keep constantly snapping together their valves, reminding one of the somewhat similar action of the birds' heads upon some of the marine polyzoa. After it has once snapped upon the fin of an unfortunate fish it appears to be quite stationary. In this condition they appear to be identical with long-known little creatures called Glochidia, from the two hooks which they possess, and deemed truly parasites. These hooks being barbed, it appears that the little mussel, having once fixed upon a fish, is unable to re-open its valves. It is not known how long they remain in this parasitic condition, nor what changes they undergo before becoming adult anodontæ.
Acclimatization of the Silk-worm.-M. Blani, of the department of Marne et Loire, describes in the Revue et Magasin de Zoologie, the success with which a species of silk-worm (Bombyx Cynthia) has been reared at Anjou. He describes the appearance presented by the worms covering the branches of trees largely cultivated for that purpose. As many as 500,000 worms were placed upon the trees, and were doing well ; most of them had changed their skin three or four times, and some were already spinning their coccoons among the leaves. The tree on which these insects feed is the Ailanthus, (natural order Xanthoxylacece), a native of China, but very hardy and easily acclimatized.
The Agricultural Society of Indre et Loire has voted a sum of money for the cultivation of the mulberry, in order to increase the food of the true silkworm (Bombyx mori).
Diseases of the Silkworm.—These occupy to a considerable extent the attention of the silk cultivator. It has recently been discovered that uric and hippuric acid in the blood of the moth is a frequent cause of sickliness. The morbid product ceases to show itself when the insects are supplied with good food in the open air.
New Mygale.-A new British species of this genus of spider has been found at Brighton-Dysdera erythrina. Previously only one was known in England. These insects are remarkable for the caves some of them construct of earth, having a distinct door or lid ; and for the probably fabulous tales of some of the larger species' propensity for catching birds.
Borings of Limnoria terebrans.—This minute crustacean, which, though only two lines in length, exists in such numbers, and is so destructive in its boring propensities, as to cause great havoc to ships and submarine wooden structures, has hitherto been supposed to have received a check from Bethell's patent creosote process. Mr. D. Stevenson has, however, stated, as the result of his experiments, that he has now ascertained beyond all doubt that creosote is not a universal or permanent preservative of timber used in marine works.
Anatomy of Sponges.—Dr. Bowerbank, who is well known to have long paid much attention to this lowly order of organisms, rejects the term Amorphozoa, or shapeless animals, proposed by De Blainville, adopting instead that of Dr. Grant, viz., Porifera, as the porous mode of imbibition of nutriment is universal in the class. He divides sponges into three classes, according to the nature of the skeleton, placing those first which contain calcareous spicula, the siliceous sponges second, and those with a horny structure, forinerly placed first, are degraded to the lowest rank.
Physiological Teaching in the Higher Schools.- Dr. Acland, Regius Professor of Medicine at Oxford, has addressed a letter to the teacher of physiology in the grammar school of Magdalen College, in which he strongly advocates physiological study; and, as the best method, he recommends the collection of the Fauna and Flora of the neighbourhood, dissections of common animals, and microscopic research. He proposes to have precise osteological monographs of common typical animals, written by experienced physiologists, and illustrated with objects, instead of plates, which, though they would be more costly, would at the same time be more durable. In connection with this subject, we may call attention to the useful and interesting series of illustrative dissections, by Mr. Charles Robertson, of the Oxford University Museum, which may be seen in the Educational Department of the Great Exhibition. These are precisely the kind of illustrations required, and might be prepared in any number by Mr. Robertson, or by Mr. Flower, of the Royal College of Surgeons.
POSTSCRIPT. Since our Astronomical Summary went to press, the following additional intelligence has been forwarded to us :
A new planet has been discovered by M. Luther, but, being near the position of the lost “ Daphne,” it has not yet been decided whether it is the latter or a hitherto unknown object.
The transits of Titan's shadow have become a matter of some curiosity during the disappearance of Saturn's ring. It has been placed beyond doubt that they are well seen even in common telescopes. On April 15, Mr. Gorton observed this phenomenon with a telescope of 3 inch aperture, and a power of 170 and afterwards of 100, and says that the shadow of this satellite was almost as easily seen as a similar appearance on Jupiter. Mr. Dawes computes the synodic period of this satellite at 15°,967. The latter observer considers, from recent observations on the ring of Saturn, that this portion is of almost inconceivable thinness, and much less than the forty miles ascribed to it by Professor Bond. Mr. Dawes imagines, also, from the appearances observed by him, “ the existence of a pretty damp atmosphere on the rings,” which, by the refraction of the light of the sun, would account for the visibility of the ring even when the illuminated surface is turned towards the earth.
Mr. Huggins draws attention to the inactive state of the clouds and belts of Jupiter in 1858 and 1859 as compared to the changes which were constantly going on during its last appearance. As both Jupiter and Saturn will be visible during the coming winter months, the beforementioned phenomenon will doubtlessengage the attention of many of our readers.
NOTES OF THE EXHIBITION—(concluded) :-
F.R.S., &c. ... ... ... ... ... ... 137
J. H. Donnelly, R.E. (Inspector of Science, South
Kensington) ... ... ... ... ... ... 155 VII.—THE ZOOLOGY AND BOTANY OF THE EXHIBITION. By
Cuthbert Collingwood, M.A., M.B., F.L.S. ... ... VIII.—THE COLONIES. By the Editor ... ... ... ... Tue MISTLETOE AND PARASITIC PLANTS ; with Page Plate. By
Mrs. Lankester... ... ... ... ... ... ... ... 196 THE WINTER LIFE OF PLANTS ; with Page Plate. By Harland Coultas 205 THE VINEGAR EEL (Anguillula aceti); with Tinted Plate. By Jabez
Hogg, F.L.S., &c. ... ... ... ... ... ... ... 213 THE EYE OF THE Ox, and its Microscopical Structure ; with a Tinted and Coloured Plate. By E. Beckitt Truman ...
... ... 220 Mars; with a Tinted and Coloured Plate. By James Breen, F.R.A.S. 228 MISCELLANEA :The British Association ; by D. T. Ansted, F.R.S.—The Zoological and Botanical Section (D); by Cuthbert Collingwood, M.A., F.I.S. Science Schools ...
. ... ... ... REVIEWS: Jeffreys' British Conchology-Simmonds' Waste Products and Unde
veloped SubstancesCooke's British Fungi-Carpenter's Revelations of the Microscope
... ... 250 SCIENTIFIC SUMMARY :Astronomy - Botany - Chemistry – Geology and Paläontology —
Mechanical Science-Medicine, Surgery, and Therapeutics—Microscopy - Mineralogy, Metallurgy, and Mining - Photography, Physics : Light, Heat, and Electricity— Zoology ...
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