The surface is faintly cancellated by slight longitudinal lines that cross growth lines which define a deep hyponmic sinus.
2.
Chambers may be simple or subdivided by secondary partitions; the surface is smooth, papillate, costate, striate, or cancellate; the aperture is simple or with an internal toothplate, entosolenian tube, or hemicylindrical structure; it may have an internal canal or stolen systems.
मोबाइल