The Principles of Biology, Volumen2

Acrogens actions agamogenesis aggregates alimentary canal arise axes axillary bud axis become bilateral symmetry bones branches canal capillaries cause cells changes chlorophyll clusters colloids colour common compound compressions connexion conspicuous continue contrast creatures degree differentiation direct equilibration distribution ends environment equal equilibrium evidence evolution exposed external facts fertility fish flowering plants flowers foliar organs fronds functions further genesis greater growing growth habitually Hence higher homologous Hydrozoa hypothesis implies incident forces increase individuals inner integration intermittent mechanical Jungermanniacea kind layer leaf leaves less liquid mass mechanical ment mid-rib mode modifications molecular morphological multiplication natural selection notochord nutrition occur ossification outer pass petioles Phænogams physiological plants portion produced radial radial symmetry relations result second order segments shape shoot sides similarly species stem stomata structure substance surface tion tissues transverse strains umbel umbellules units unlike vascular vertebral column Vertebrata vessels