Types.- Holotype from Black Booby Cay (West Booby), Atwoods or Samana group,
Remarks.- This species possesses a general outline similar to C. utowana (East Plana Cay) but differs from that species in being a little smaller, colored a flat white, having a coarse sculpture of heavy ribs and being entirely imperforate.
Other than a little variation in size, this colony of greenwayi is strikingly uniform. An occasional specimen is found to be very faintly mottled on the second to fourth whorls. C. utowana on the other hand is strongly mottled, the mottled specimens possess bars of color on all whorls beyond the first 2½. The two dead specimens of C. greenwayi from Atwood's Cay are similar in all respects to those of Black Booby Cay." (Clench, 1934:207)
Clench (1963:409) noted that "only dead or very old specimens of this species were found on West Plana Cay by Bartsch in 1930. Several different forms occurred from typical costate greenwayi to nearly smooth, slender or very stout specimens which approximate C. utowana Clench from East Plana Cay. It is impossible to tell whether or not these specimens existed at one time or represent populations which existed at different times."