Vair represents the winter coat of the red squirrel, which is blue-grey on top and white underneath. To form the linings of cloaks, the pelts were sewn together, forming an undulating, bell-shaped pattern, with interlocking light and dark rows. The heraldic fur is depicted with interlocking rows of argent and azure, although the shape of the pelts, usually referred to as "vair bells", is usually left to the artist's discretion. In the modern form, the bells are depicted with straight lines and sharp angles, and meet only at points; in the older, undulating pattern, now known as "vair ondé" or "vair ancien", the bells of each tincture are curved and joined at the base. There is no fixed rule as to whether the argent bells should be at the top or the bottom of each row. At one time vair commonly came in three sizes, and this distinction is sometimes encountered in continental heraldry; if the field contains fewer than four rows, the fur is termed "gros vair" or "beffroi"; if of six or more, it is "menu-vair", or miniver.