MACROSCHISMA. 193 



M. dilatata A. Adams. PI. 59, fig. 63. 



Shell ovate-oblong, radiately costate, red variegated with white, 

 rounded all around ; sides dilated ; foramen oblong, narrowed in 

 the middle. (Ad.) 



Habitat unknown. 



M. dilatata Ad. P. Z. S. 1850, p. 202.— Sown. Thes. iii, p. 206, 

 f. 220. 



M. rirATULA Swainson. PI. 59, figs. 30, 31. 



Shell ovate-oblong, radiately costellate, brown, subdepressed, the 

 sides concave, all over rounded ; foramen large, oblong, posteriorly 

 dilated ; posterior extremity much elevated, margin scarcely sinuous. 

 (Ad.) 



Habitat unknown. 



M. hiatula Swainson MalacoL p. 356.— Ad. P. Z. S. 1850, p. 

 202. — Fissurella macroschisma Sowb. Genera of Shells, Fissurella 

 fig. 5. 



This species has the slit rather narrow, not much dilated pos- 

 teriorly. 



M. compressa A. Adams. PI. 59, fig. 64. 



Shell narrowly oblong, white radiately painted with rose, decus- 

 sated by granulose riblets and concentric stria?, rounded, the back 

 convex, sides compressed, inflexed in the middle; posterior ex- 

 tremity much elevated ; foramen large, lanceolate, posteriorly 

 dilated. (Ad.) 



Suez. 



M. compressa Ad. P. Z. S. 1850, p. 202.— Sown. Thes., p. 205, f. 

 218— Fischer, Journ. de Conchyl. 1871, p. 210. 



M. megatrema A. Adams. PI. 59, fig. 32. 



Shell ovate-oblong, white, radiately painted with rose ; sculptured 

 with rugose riblets and concentric stria? ; back subelevated, sides 

 plan ul ate ; foramen ovate, lanceolate, very large. (Ad.) 



Habitat unknown. 



M. megatrema Ad. P. Z. S. 1850. — Sowerby, Thes., p. 205, f. 

 227. 



M. cuspidata A. Adams. PI. 59, fig. 60. 



Shell ovate-oblong, anteriorly narrowed, produced, acuminate; 

 posteriorly elevated, rounded ; margin deeply undulating ; brown 

 13 



