The Monthly Microscopical Journal: Transactions of the Royal Microscopical Society, and Record of Histological Research at Home and Abroad, Band 5Robert Hardwicke, 1871 |
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Häufige Begriffe und Wortgruppen
19th band achromatic acid angle angular aperture animal Annelids aperture aplanatic aplanatic searcher Ascaris balsam body Canada balsam cells chitinous cilia colour correct cover Crustacea Degeeria described diameters diatoms disk Ecistes examination exhibited experiments eye-piece fibres filaments focus give glass globule hairs Hennah illumination immersion lens inch insect instrument lateral bands layer lenses Lepidocyrtus Lepidoptera leptothrix light lines longitudinal markings meeting membrane microscopists minute Monthly Microscopical Journal nature object-glass objects oblique observed obtained optical organisms paper Paramecium particles pharynx photographs pigment Pigott placed plants plate Podura scale points polariscope portion Powell and Lealand present prism produced rays refraction refractive index remarks ribs rotifer ROYAL MICROSCOPICAL SOCIETY searcher seen side silica slides solution species specimens spores striæ structure surface thickness thin Thysanura tion tissue transverse tube Vorticella water vascular system Wenham Wonfor Woodward
Beliebte Passagen
Seite 111 - With organic chemistry, molecular physics, and physiology yet in their infancy, and every day making prodigious strides, I think it would be the height of presumption for any man to say that the conditions under which matter assumes the properties we call " vital " may not, some day, be artificially brought together.
Seite 100 - raised in the garden of the Horticultural Society from seeds taken from the stomach of a man, whose skeleton was found thirty feet below the surface of the earth, at the bottom of a barrow which was opened near Dorchester. He had been buried with some coins of the Emperor Hadrian ; and it is therefore probable that the seeds were sixteen or seventeen hundred years old...
Seite 262 - We come now to a still more extraordinary part of the imitation, for we find representations of leaves in every stage of decay, variously blotched and mildewed and pierced with holes, and in many cases irregularly covered with powdery black dots gathered into patches and spots, so closely resembling the various kinds of minute fungi that grow on dead leaves that it is impossible to avoid thinking at first sight that the butterflies themselves have been attacked by real fungi.
Seite 222 - ... varying temperature of its different sides. Moreover, as soon as the polished surface of a building is made rough from any of the causes aforementioned, the seeds of minute lichens and mosses, which are constantly floating in the atmosphere, make it a place of repose, and by the growth and decay of the microscopic plants which spring from these, discoloration is produced, and disintegration assisted.
Seite 32 - ... slender optic nerves, and indicates a general similarity in the nervous system. The genital organs of the trilobites were probably very similar to those of Limulus, as they could not have united sexually, and the eggs were probably laid in the sand or mud, and impregnated by the sperm cells of the male, floating free in the water. The muscular system of the trilobites, must have been highly organized as in Limulus, as like the latter they probably lived by burrowing in the mud and sand, using...
Seite 223 - II. Professor Haeckel looks upon the causes which have led to the present diversity of living nature as twofold. Living matter, he tells us, is urged by two impulses : a centripetal, which tends to preserve and transmit the specific form, and which he identifies with heredity; and a centrifugal, which results from the tendency of external conditions to modify the organism and effect its adaptation to themselves. The internal impulse is conservative, and tends to the preservation of specific, or individual,...
Seite 32 - The trilobitic character of the body, as shown in the prominent cardiac and lateral regions of the body, and the well-marked abdominal segments of the embryo, the broad sternal groove, and the position and character of the eyes and ocelli, strengthen this view. The organization and the habits of Limulus throw much light on the probable anatomy and habits of the Trilobites. The correspondence in the cardiac region of the two groups shows that their heart and circulation was similar. The position of...
Seite 31 - Limulus doubles in size. Conclusions. The eggs are laid in great numbers loose in the sand, the male fertilizing them after they are dropped. This is an exception to the usual mode of oviposition in Crustacea; Squilla and a species of Gecarcinus being the only exception known to me to the law that the Crustacea bear their eggs about with them. Besides the structureless, dense, irregularly laminated chorion, there is an inner egg membrane composed of rudely hexagonal cells; this membrane increases...
Seite 31 - Gecarcinus being the only exception known to the author to the law that the Crustacea bear their eggs about with them. Besides the structureless, dense, irregularly laminated chorion, there is an inner egg membrane composed of rudely hexagonal cells ; this membrane increases in size with the growth of the embryo, the chorion splitting and being thrown off during the latter part of embryonic life.
Seite 32 - It differs from the adult simply in possessing a less number of abdominal feet (gills), and in having only a very rudimentary spine. Previous to hatching, it strikingly resembles Trinucleus and other trilobites, suggesting that the two groups should, on embryonic and structural grounds, be included in the same order, especially now that Mr. E. Billings has demonstrated that Asaphus possessed eight pairs of five-jointed legs of uniform size.