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Geological Survey Professional Paper 294—K
The Rocks and Fossils of Glacier National Park: The Story of Their Origin and History |
APPENDIX D: Key to the identification of fossil algae in the Belt series of Glacier National Park
| I. Incrusting forms, growth upwards from a point on the substratum by the addition of convex upward laminae Genus: Cryptozoon | ||||
| A. Gross form turbinate. | ||||
| 1. Laminae conform to upper surface of colony in later stages of development. | ||||
| a. Laminae smooth | Cryptozoon occidentale, figure 126 | |||
| II. Incrusting forms, growth upwards from a surface on the substratum by the addition of convex upward laminae Genus: Collenia | ||||
| A. Gross form hemispheroidal or depressed spheroidal. | ||||
| 1. Laminae conform to upper surface of colony. | ||||
| a. Laminae coarsely crenulate | Collenia undosa, figure 132 | |||
| b. Laminae smooth | Collenia symmetrica, figure 133 | |||
| 2. Laminae conform to upper surface of colony only during later stages of development. | ||||
| a. Laminae finely crenulate | Collenia multiflabella, figure 127 | |||
| B. Gross form irregularly cylindroidal. | ||||
| 1. Laminae flattened to strongly convex. | ||||
| a. Laminae smooth | Collenia frequens, figure 136 | |||
| III. Colonies of nested conical laminae with basal apex attached to the substratum Genus: Conophyton | ||||
| A. Gross form cylindroidal. | ||||
| 1. Axes of cylindroids at a low angle to bedding. | ||||
| a. Laminae smooth | Conophyton inclinatum, figures 134, 135 | |||
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Last Updated: 08-Jul-2008