A Course of Practical Instruction in Elementary BiologyMacmillan and Company, 1876 - 279 páginas |
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Términos y frases comunes
abdominal acid adductor animal antheridia antherozooids aortic arch aperture appendages archegonia artery attached axis become blood body bone branches canal carbonic anhydride cartilage cavity cells chamber chlorophyll chromic acid cilia colour colourless containing cord dissect divided division dorsal edge elongated epidermis examine exoskeleton external fibres filaments fluid free end Frog front ganglia ganglion gills give rise granular granules heart high power Hydra hypha hyphæ inch obj inner integument internodes intestine layer limbs lobes Lobster mass maxilla median membrane middle line mouth muscles nerve Note nucleus organs outer oval pair papillæ passes pericardium peristome plant posterior end prothallus Protococcus protoplasm rectus internus rounded running seen side skull solution somites specimens spinal sporangia sporangium spores stem stomach structure surface terminal thick thin tissue Torula transparent transverse section trunk tube urostyle valves vein ventral ventricle vertebral vertebral column vessels Vorticella walls yeast
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Página v - They are, in fact, branches from the common stem of Biology, and neither can be rightly conceived without bearing this in mind. Now I maintain that for still stronger reasons the several branches of social science must be kept in the closest relation.
Página 20 - The amoeba is an animal, not because of its contractility or power of locomotion, but because it never becomes enclosed in a cellulose sac, and because it is devoid of the power of manufacturing protein from bodies of a comparatively simple chemical composition. The amoeba has to obtain its protein ready made, in which respect it resembles all true animals, and therefore is, like them, in the long run, dependent for its existence upon some form or other of vegetable life.
Página 73 - Thus new cells are continually being added, on the inner side of the cambium layer, to the thickness of the wood, and on the outer side of it, to the thickness of the bark; and the axis of the plant continually increases in diameter, so long as this process goes on. Plants in which this constant addition to the outer face of the wood •and the inner face of the bark takes place, are termed exogens. • At the apex of the stem, and at that of the root, the eambium layer is continuous with the cells,...
Página v - Martin and published in 1876: Some twenty years ago, I arrived at the conviction that the study of living bodies is really one discipline, which is divided into zoology and botany simply as a matter of convenience ; and that the scientific zoologist should no more be ignorant of the fundamental phenomena of vegetable life, than the scientific botanist of those of animal existence.
Página 108 - This adduction results from the contraction of two thick bundles of muscular fibres, which pass from the inner face of one valve to that of the other, one at the anterior and the other at the posterior end of the body, and are called the anterior and posterior adductors. The valves of the dead Anodonta always gape, and if they are forcibly shut they spring open again.