On Growth and Form, Volume 2

according actual already angle animal appearance arrangement axis beautiful become begin body bone bubbles called cells centre chambers closely common compared complex constant constitute construction continuous coordinates corners corresponding curvature curve described determined diagram direction divided drop edges equal explain fact figure fluid follows forces four further growing growth hexagonal horn illustrated increase instance latter less lines logarithmic mathematical means measured mechanical meet natural nearly obvious organism original outer particular partition pattern phenomenon physical plane portion position possible precisely pressure principle problem ratio regular relation remain represented result round seen separate shape shell shew short side similar simple single skeleton solid space speak species spherical spicules spiral structure successive surface symmetry tend tension thing triangle various vary walls weight whole whorls