Figures

Figure 15.26   Graptolite life modes: 1, conical forms with spiral motion; 2, fl at or slightly conical forms with slow, slightly spiral velocities; 3, mono- or biramous forms with spiral movement due to asymmetry; 4, forms with high angles between stipes having linear movement; 5, straight forms with mainly linear descent. (Based on Underwood 1994.)

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