A Monograph of the Fresh-water Polyzoa: Including All the Known Species, Both British and Foreign |
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which I could not find connected by intermediate gradations with other forms , and which could not , with probability , be referred to the accidental influence of external agencies . It is possible that some of the forms here described ...
which I could not find connected by intermediate gradations with other forms , and which could not , with probability , be referred to the accidental influence of external agencies . It is possible that some of the forms here described ...
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Numerous systems were accordingly from time to time proposed , which , however , were all more or less artificial , and involved the fundamental error of assuming the external calcareous or horny covering as a character of primary ...
Numerous systems were accordingly from time to time proposed , which , however , were all more or less artificial , and involved the fundamental error of assuming the external calcareous or horny covering as a character of primary ...
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Further , let us imagine the digestive tube thus constituted to be suspended in a fluid contained in a membranous sac with two openings , one for the mouth and the other for the vent ; the tentacula alone being external to the sac .
Further , let us imagine the digestive tube thus constituted to be suspended in a fluid contained in a membranous sac with two openings , one for the mouth and the other for the vent ; the tentacula alone being external to the sac .
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The cœnocium is composed almost universally of two perfectly distinct tunics ; to the external I have given the name of Ectocyst , ‡ and to the internal that of Endocyst . The sort of disc or stage which surrounds the mouth and bears ...
The cœnocium is composed almost universally of two perfectly distinct tunics ; to the external I have given the name of Ectocyst , ‡ and to the internal that of Endocyst . The sort of disc or stage which surrounds the mouth and bears ...
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The attachment of the endocyst to the base of the tentacular crown closes the cœnœcial chambers externally , while the polypide is thus suspended in the midst of the fluid with which these chambers are filled .
The attachment of the endocyst to the base of the tentacular crown closes the cœnœcial chambers externally , while the polypide is thus suspended in the midst of the fluid with which these chambers are filled .
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Otras ediciones - Ver todas
A Monograph of the Fresh-water Polyzoa: Including All the Known ..., Tema 28 George James Allman Vista de fragmentos - 1856 |
A Monograph of the Fresh-Water Polyzoa, Including All the Known Species ... George James Allman Sin vista previa disponible - 2009 |
Términos y frases comunes
action adherent admit Alcyonella alimentary canal Allman already anatomy animal appearance Ascidian attached become Beneden bodies branches branchial British cavity cell character cilia closely complete condition connected consists constitutes contained continuous corresponding Cristatella described detected disc distinct Dumortier ectocyst edit endocyst entire epistome examined existence extending external extremity fibres fluid Fredericella fresh-water Polyzoa genera genus Gervais gives Hancock Hist important internal latter layer Leidy lophophore Lophopus margin mass Mém membrane memoir minute mouth muscles Natural naturalists nearly observed occur organ orifice Original figures Paludicella passes Plumatella Plumatella repens Polype polypide Polyzoon portion present published relations repens resemblance retraction retractor Rösel seen separated sheath side space species specimens statoblasts stomach stones structure surface surrounding tentacula transparent transverse Trembley true tubes Tubularia tunic Tunicata walls whole young