The Staircase Shells. Ladder Shells. Wentletraps 



was cut in two. The clever Chinese counterfeited the precious 

 shells, too rare for their liking, by moulding them from a paste 

 made of rice flour. Now the range of the species is found to be 

 much less restricted than was supposed in the eighteenth century. 

 A good specimen of S. pretiosa can be had of almost any curio 

 dealer for a dollar or two. 



The Ladder Shell (5. Groenlandica, Chemn.), Greenland to 

 Massachuetts Bay, has been found abundantly in the stomachs of 

 fishes taken on the Grand Banks and farther south. The shells 

 are picked up on Nahant beach and on the Maine coast. They are 

 graceful, turreted, heavy, with sharp spire of ten whorls, flattened, 

 close-set, each bearing revolving ridges and crossed by oblique, 

 prominent white ribs. The ground colour is brown or bluish. 

 A rib, angled at the inner point, edges the round aperture. 



The animal is yellowish gray, splotched with white. The 

 foot is squarish and thick. The head is rounded above, elongated, 

 with a shiny black eye at the base of each short tentacle. The 

 large mouth eagerly seizes bits of fresh beef, when the mollusk is 

 in an aquarium. Its movements are sluggish. Length, i inch. 



S. lineata, Say, found from New England to Florida, is a 

 thick little ladder shell ornamented with two brown spiral bands 

 on the body whorl. The shell is elongated, with six or seven 

 whorls, and regular cross ribs throughout its length. Length, 

 about h inch. 



S. angulata, Say, with its ribs a bit angled next to the 

 suture above, has six to ten whorls which do not touch each other 

 in the coil. It is about | inch long, rather stout and white. It 

 occurs from Connecticut to Florida and Texas. 



S. multistriata, Say, of our Atlantic coast, is known by the 

 multitude of its ribs that crowd closer than in any other species. 

 It is a solid white shell of graceful form. Length, -| to f inch. 



S. clathratula, Ads., found on European coasts, and from 

 New England to Cape Hatteras, is a polished white, almost trans- 

 parent shell, slender and graceful, about h inch long. Its 

 rounded whorls bear a great number of cross ridges. 



On the west coast is found S. Hindsii, Cpr., a delicate white 

 ladder shell, scarcely an inch long, with a needle point and 

 rounded whorl crossed by many thin, sharp ridges. Professor 

 Keep says these shells are mounted for ear drops, sometimes, 

 by enterprising jewellers. Southern California. 



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