in geometry, the circumference of a circle, ellipsis, or any other regular curvilinear figure.

PERILOCA, Virginian silk, a genus of the digynia order, belonging to the pentandria class of plants. There are four species, all of them natives of warm climates. They are perennial shrubby plants with turning branches, rising from three to 40 feet high, adorned with white and purple flowers. The seeds are inclosed in capsules filled with a soft down. Two of the species, viz. the Graeca and Africana, will live in the open air in this country, and are propagated by layers;