154 SYSTEMATIC PALEO^'TOLOGY 



Mangtlia parvoidea n. sp. 

 Plate XLII, Fig. 3. 



Description. — Shell small, fusiform, seven-whorlecl ; whorls very con* 

 vex, with numerous faint oblique longitudinal ril)s and almost obsolete 

 closely set spiral striae ; apex of spire obtuse. 



This species has somewhat the general appearance of M. parva, with 

 which it is associated and has been confused. It is less slender than 

 parva (very much so in the spire), less constricted at the suture, and 

 has less prominent ribs. It also lacks the abrupt angularity of that 

 species and is generally larger. 



Length, 10 mm. ; diameter, 4 mm. 



Occurrence. — St. Mary's Formatiox. St. Mary's Eiver. 



Collections. — Maryland Geological Survey, Johns Hoi^kins University, 

 Cornell University. 



Maxgilia corxelliaxa n. sp. 

 Plate XLII, Fig. 4. 



Description. — Shell small, slender, fusiform, eight-whorled ; whorls 

 moderately convex; body whorl with about twelve obtuse longitudinal 

 ribs ; near the center of each whorl are two equally prominent raised re- 

 ^'olving ribs with a very fine one between them, and on either side of 

 them about four other spiral ribs intermediate in size between them and 

 the medial one ; lines of growth faint ; sinus not deep ; beak short, slightly 

 curved, and strongly striated. 



Length, 8 mm.; diameter, 2 mm. 



Occurrence. — Calvert Formation. Plum Point. 



Collection. — Cornell University. 



Mangilia patuxentta n. sp. 



Plate XLII, Fig. 5. 



Description. — Shell small, fusiform, five-whorled (without the two- 

 Avhorled nucleus) ; later whorls strongly rugose, with 9 to 11 sharply 

 elevated costae crossed by two or three elevated revolving lines on each 

 whorl of the spire and by many more on the body whorl ; revolving lines 



