The Olive Shells. Rice Shells. Harp Shells 



in the typical form. The colour is slightly faded in three re- 

 volving bands. Fine lines, gathered as if into fringes edge the 

 sutures. The columellar folds are numerous; only the anterior 

 ones are strong. The apex is elongated. 



From the type, divergence in colour is great, leading from 

 dark rich brown to white. But the netted pattern is rarely lost 

 or covered up. The shells are heavy. Length, i J to 2 J inches. 



Habitat. — West Indies, Florida. 



The west coast form of the netted olive is O. araneosa, Lam., 

 a somewhat larger, broader shell, and less cylindrical, being 

 swollen above the middle. The spire is prominent; the body 

 whorl drawn in below the narrow suture. The creamy ground 

 is overlaid with chestnut or darker brown in zigzag series of 

 indistinct spots. 



Habitat. — Panama to Lower California. 



The LfCttered Olive (0, litterata, Lam.) is slender and tapers 

 toward both extremities. The creamy ground colour bears a close 

 netted pattern in pale brown spiral bands separating the brighter 

 ones. Here and there are dark figures suggesting printed char- 

 acters or hieroglyphics. 



The narrowing anterior end of the shell separates this species 

 (and not very satisfactorily) from 0. reticularis. The aperture 

 is lined with violet, sometimes faded almost to white in cabinet 

 specimens. 



These polished olive shells, i^ to 2^ inches long, are picked up 

 on sand beaches from Beaufort, N. C, to Key West, and through- 

 out the West Indies. They apparently live in colonies. I have 

 found them alive on the inland beaches of Marco Bay, on the West 

 coast of Florida. The two thin reflexed mantle flaps and the 

 broad foot have the same colours and markings as the shell, and 

 blend well with the wet sand and gravel as the creature ploughs 

 along, half-buried, to overtake the receding water. Probably 

 the small thin-shelled bivalves met on the way furnish daily 

 rations of fresh meat. 



These "Panama shells" are collected and strung to make 

 portiferes which sell at good prices to Northern tourists. 



Three species are markedly different in shape from the typical 

 cylindrical olive shell. 



The Fusiform Olive (0. fusiformis, Lsm.) is broad shouldered 

 with a tapering spire and base. Its pale surface is marked with 



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