Zooecial Aperture Shape
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Very Round or Circular |
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Round |
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Subround |
  |
Angular |
  |
Subangular |
 |
Polygonal |
 |
Subpolygonal |
 |
Rhombic |
  |
Quadratic |
| |
Very Round or Circular |
| |
Round |
| |
Subround |
| |
Angular |
| |
Subangular |
| |
Polygonal |
| |
Subpolygonal |
| |
Rhombic |
| |
Quadratic |