Cassidulina

Cassidulina is a foraminiferal genus described in the Treatise Part C. (Loeblich & Tappan, 1964), as having a free, lenticular test, with central boss of clear calcite on either side. Chambers are biserially arranged, enrolled planispirally with a subangular to keeled periphery. The wall is calcareous, hyaline (glassy), optically granular, perforate. The surface is smooth with a polished appearance. Sutures are radial to oblique, straight or curved. The aperture is a narrow arched slip at the base of the apertural face, partly closed by an apertural place. (Loeblich and Tappan 1988)