Quincuncial : Having the form of a quincunx.

Quincuncial : Having the leaves of a pentamerous calyx or corolla so imbricated that two are exterior, two are interior, and the other has one edge exterior and one interior; as, quincuncial aestivation.

Example:


Taxonomy
projection, Peirce, quincuncial, square, hemisphere, sphere, stereographic projection, C. S. Peirce, map, Charles Sanders Peirce, projection maps, free encyclopedia, conformal map projection, Snyder, History, complex plane, the hemisphere, elliptic function.

Defination from the web:
quincuncial projection is a conformal map projection (except for four points where its conformality fails) that presents the sphere as ... In effect, the whole map is a square, inspiring Peirce to call his projection quincuncial, after the arrangement of five items in a quincunx. ...