276 American Seashells 



7 to lo mm. in length, very similar to punctostriatus, but larger, very 

 much thicker-shelled, glossy, opaque milk-white with light orange-brown 

 suffusions on the body whorl. Commonly dredged in a few fathoms of 

 water. 



Fa77nly RINGICULIDAE 

 Genus Rmgiciila Deshayes 1838 



Ringicula se77nstriata Orbigny Orbigny's Helmet-bubble 



Plate 26V 



North Carolina to southeast Florida and the West Indies. 



2 to 3 mm. in length, thick-shelled, resembling a miniature Phalium or 

 Scotch Bonnet. 4 globose whorls, spire elevated. Aperture oblong; columella 

 thickened by 3 folds, i above, 2 below. Outer lip very thick, swollen in the 

 middle by a large tooth. Whorls, white, smooth, except for fine striations 

 on the base. Not uncommonly dredged from 34 to 107 fathoms. 



R. nitida Verrill (Verrill's Helmet-bubble from Maine to the Gulf of 

 Aiexico. 100 to 500 fathoms) is exteriorly smooth, with a simple, thickened 

 outer lip, and with 2 smaller, spiral ridges on the columella. 



Family HYDATINIDAE 

 Genus Micromelo Pilsbry 1894 



Micromelo undata Bruguiere Miniature Melo 



Plate 26U 

 Lower Florida Keys and the AVest Indies. 



V2 inch in length, oval, rather thin and moderately fragile. Characterized 

 by its whitish to cream color overlaid by 3 widely spaced, fine spiral lines 

 of red and by many or few axial, wavy, lighter red flammules or lines. Un- 

 common. Found at low tide. 



Genus Hydatina Schumacher 18 17 

 Hydatina vesicaria Solander Brown-lined Paper-bubble 



Plate i3q 

 South half of Florida and the West Indies. 



I to I ^ inches in length, very thin, fragile, globose. Periostracum thin, 

 buff to greenish. Shell characterized by many close, wavy, brown spiral 

 lines. Animal large and colorful. Foot very broad. Moderately common in 

 certain shallow, warm-water areas where they burrow in silty sand. For- 

 merly called H. physis Linne which, however, is believed to be limited to 

 the Indo-Pacific. 



