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the muscles of the pelvis swells the first intercostal plates, forming a very 

 strong elevated rib across the costals, branching laterally from the scapula? to 

 the arms, at the same time that an elevated ridge is formed over the intercos- 

 tals, connecting laterally with the ridge noticed before, extending to the orifice 

 in the integument or mouth and rendering it subpentangular, (fig. 4.) 



Should the variety pointed out above in the columnar formation, at a fu- 

 ture time enable me to establish two species, I should propose for that from 

 Mitchel Dean, the name of Rhodocrinites quinquangularis. 



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