178 PROCHEDINGS OF THE NATIONAL MUSEUM. VOL. 37. 
FISSURELLA PERUVIANA Lamarck. 
Fissurella peruviana LaMaRrcK, Anim. s. Vert., vol. 7, 1822, pt. 2, p. 15 (not or 
DevessEeR?, Rec., pl. 24, fig. 7).—Rexnve, Conch. Icon., 1849, Fissurella, 
fig. 26. 
Lapa. Dredged in Callao Harbor on the northeast side of San Lorenzo Island, 
in 24 fathoms. 
Distribution.—The whole Peruvian province. 
Shell rounded oval, elevated, conical, the foramen small, a little 
in advance of the middle; radiately finely striated; inside white, the 
margin alternately red and gray; outside red toward the summit, 
becoming more purple and darker toward the base; the margin is 
smooth, with a dark border inside, the exterior rayed with dark 
purple. Length about 30 mm. 
This is the F’. occidens of Gould. 
' MEGATEBENNUS COKERI, new species. 
Plate 24, figs. 3, 7. 
Lobos de Afuera Island, on beach. 
Shell’ ovate, narrower in front, solid, heavy, steep sided, anterior 
slope shorter, sharply radially sulcate, the interspaces flattish, feebly 
rounded, not uniform in width; lines of growth looped toward the 
apex over the interspaces; color greenish white toward the base, 
reddish purple toward the apex, with sparse rays of the latter color; 
foramen large, keyhole shaped, with a greenish margin; length of 
foramen at the outer margin nearly one-third of the total length of 
the shell; interior greenish white, with a polished, greenish, radiately 
striate margin to the foramen; margin of the base smooth, entire, 
extended for a narrow space over the exterior edge. The type 
(Cat. No. 207744, U.S.N.M.) measures: Length of shell 27.5; of outer 
edge of foramen 9.0; of inner edge of same 6.0; of foraminal inside 
margin 11.0; maximum width of shell at the posterior edge of the 
above margin 16.5; at the anterior edge of the above margin 14.0; 
height of the shell 10.0 mm. 
This species unquestionably belongs to Pilsbry’s section Ambly- 
chilepas, which was supposed to be wholly old world in its distribu- 
tion. It much resembles M. scutellum (Gmelin) Pilsbry, but is 
darker toward the summit and lighter toward the base, while in the 
Cape of Good Hope species the reverse coloration obtains. 
Named for Mr. R. E. Coker. 
ACMAA VIRIDULA Lamarck. 
Plate 24, figs. 1, 2. 
Patella viridula Lamarck, Anim. s. Vert., vol. 7, 1822, p. 539.—DELESSERT, 
Ree. Coq., pl. 23, fig. 2: 
Acmzxa pretrei OrBiGNY, Voy. Am. Mér., vol. 5, 1841, p. 481, pl. 78, figs. 15-16. 
Patela. From rocky shore on the northeast side of San Lorenzo Island, Callao 
Bay; similar stations on Lobos de Afuera Island; the Pescadores Islands; Sechura 
