The Periwinkles and Chink Shells 



L. variegata, Cpr., streaked with chestnut, often beaded 

 with white on the peripheral margin, has about the same distri- 

 bution, but is one-half as large as L. porrecta. 



L. pallidula, Da C, with widely flaring mouth and wide 

 umbilicus, is a yellowish species found in the North Atlantic. 

 It is about J inch in diameter. 



Habitat. — New England. 



L. divaricata, Fab., is a glossy little chink shell, with elon- 

 gated spire, whitish, often variously banded with brown and 

 white. Length, about i inch. 



Habitat. — All cold waters of northern hemisphere, including 

 New England and northwestern coast. 



Genus MODULUS, Gray- 

 Shell top-shaped, solid; whorls grooved and tubercled; 

 umbilicus narrow; columella grooved, ending below in a sharp 

 tooth. Few species. 



The Florida Modulus (M. Floridanus, Conr.) has a depressed 

 spire, strongly ribbed, and crossed above the periphery by short, 

 oblique nodular ridges. The umbilicus and the sharp tooth of 

 the columella are the best distinguishing features. Its colour is 

 dirty white, often tinged with brown or olive green. Diameter, 

 i to f of an inch. 



Habitat. — West coast of Florida Keys. 



Genus FOSSARUS, Phil. 



Shell small, spiral, compact, ridged, with umbilical groove 

 on the columella. Littorine mollusks on seaweeds. 



The Elegant Fossarus (F. elegans, Verr.) has its few coils 

 most beautifully sculptured with strong winding ridges crossed 

 by deeply chiseled, close striations. The large, round mouth 

 crowds the grooved columella and almost covers the pit. The 

 outer lip is frilled. Length, J inch. 



Habitat. — Rhode Island to Cape Fear. 



F. obtusus, Cpr., is a light brown, round shell, with spiral 

 grooves that crimp the lip of the oval aperture. The umbilical 

 chink is present, though small. Length, \ . inch. 



Habitat. — California. 



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