| 1. | The U shaped body chamber has coarser ribbing and large tubercles.
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| 2. | These are slender, elongate shells with the middle of the body chamber lirae.
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| 3. | The body chamber is inflated, dorsal and ventral profiles both convex.
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| 4. | The body chamber in the adult is contracted toward the aperture.
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| 5. | The camerae ( chambers ) and body chamber are short.
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| 6. | The body chamber is attached at knee-like bends on the ventral and lateral sides.
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| 7. | The body chamber is one half the overall shell length.
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| 8. | The body chamber is smooth with a rounded venter.
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| 9. | Of course the collar seal is still applied, so that the body chamber remains airtight.
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| 10. | Body chambers are reduced in size and are excentric.
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