536 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



BANKIA (NEOBANKIA) JOHNSONI, new species 



Johnson's shjpwokm 

 Plate 53, figs. 5, 13; plate 56, fig. 7; plate 58, figs. 10, 11, 12 



Shell of moderate size, subglobular. The anterior area and the 

 anterior median area flesh-colored. The middle median area tinted 

 with the same shade, the rest white. The extreme anterior area is 

 marked by the usual sinus, which is covered by a white callus, which 

 is reflected slightly over the anterior portion. From this callus the 

 dental ridges radiate backward, curving abruptly downward at the 

 extreme anterior portion and then gently backward. These ridges 

 are about half as wide as the spaces that separate them on the early 

 portion of the shell, but become closer spaced as the shell increases 

 in age. The later ridges are separated by mere impressed grooves. 

 The ridges slope more abruptly dorsally than ventrally and are finely 

 denticulated at their free margin. There are 56 present in the type. 

 The line marking the junction of the anterior area and the anterior 

 median portion is wavy. The anterior median portion is rather 

 broad, marked by rather broad denticulated ridges, which meet the 

 dental ridges of the anterior area in a little more than a right angle. 

 There are 28 of these in a line parallel to the ventral border of the 

 anterior part. The middle median portion is slightly concave and 

 crossed by rather strong, irregularly spaced lines of growth. The 

 posterior median portion is almost as wide as the anterior and middle 

 portion combined, and is marked by fine lines of growth only. The 

 junction of the posterior part and the posterior median portion is 

 marked by a strong constriction. The posterior part or auricle appears 

 without sculpture. The interior of the shell is bluish white. The 

 junction of the anterior and median parts is marked by a tumid ridge. 

 The middle median portion is a rough depressed groove, at the tip 

 of which the usual knob is present. The posterior part overlaps the 

 posterior median portion as a strong spoonlike shelf, half of which 

 projects outward and half inward, leaving a decided cavity. The 

 blade is broad, irregularly roughened at the anterior margin and 

 extends for two-thirds of the length of the shell, springing from under 

 tfo !bone The pullets are unfortunately fractured in all the spec- 

 in are of the cone-in-cone type, with 



tli la ted all around. 



i, U.S.N.M.) was collected by the 

 Ui ^s Steamer Albatross Philippine Expe- 



di athoms in a piece of wood taken on 



m uzon. The shell measures: Altitude, 



4.. ter, 4.4 mm. The pallet is too broken 



to 



s taken from the same chunk of wood 

 is 3, U.S.N.M. Still another lot was 



