LITTORINIDAE 13 3 



Littorina angulifera Lamarck Angulate Periwinkle 



Plate 19a 



South half of Florida, the West Indies and Bermuda. 



About I inch in length; thin-shelled but strong. First two or three 

 whorls smooth, remainder with many fine, spiral grooves. Last whorl some- 

 times carinate. Color variable — whitish, yellowish or orange- to red-brown 

 with darker, wavy, vertical, oblique stripes. Columella pale purplish with 

 whitish edges. Operculum pale-brown. Common in mangrove areas where 

 the waters are calm and brackish. It is found high above the high-tide mark 

 clinging to wharf pilings, and is often seen on the trunks and branches of 

 mangrove trees. Introduced to the Pacific side of the Panama Canal. L. 

 scabra Linne is from the Indo-Pacific. 



Littorina obtiisata Linne Northern Yellow Periwinkle 



Plate igf 



Labrador to Cape May, New Jersey. Northwest Europe. 



/i to % inch in length, equally wide, with a low spire; smoothish. Color 

 variable but usually a uniform, bright, brownish yellow or orange-yellow. 

 Sometimes with a white or brown spiral band. Columella whitish. Oper- 

 culum bright yellow to orange-brown. This is L. palliata Say. A common 

 coastal species associated with rockweeds. 



Littorina mespilhvm Miihlfeld Dwarf Brown Periwinkle 



Plate 19k 



Florida Keys and the Caribbean Area. 



M inch in length, somewhat shaped like obtusata. Characterized by its 

 dark-brown periostracum, glossy-brown columella and aperture, by its tiny, 

 chink-like umbilicus, and by the presence, in some specimens, of rows of 

 small, round blackish spots. Common in "splash-pools" from high-tide line 

 to 6 or 7 feet above. 



Littorina saxatilis Olivi Northern Rough Periwinkle 



Plate i9d 



Arctic Seas to Cape May, New Jersey. Arctic Seas to Puget Sound. 



% to /4 inch in length, resembling a "distorted, small L. littorea.^^ 

 Adults characterized by poorly developed, smoothish, fine spiral cords. Color 

 drab gray to dark-brown. Interior of aperture chocolate-brown. Females 

 give birth to live, shelled young. Often found with L. obtusata, but not so 

 common. This is L. rudis Maton and L. groenlandica Menke. 



