Note: It has a large air sac, or float, with a sail-like crest on its upper side. Numerous zooids of different kinds are attached to the under side of the float. Some of the zooids have very long tentacles; some have a mouth and digest food; others produce gonophores. The American species (Physalia arethusa) is brilliantly colored, the float being pink or purple, and bright blue; the zooids blue. It is noted for its virulent stinging powers, as well as for its beautiful colors, graceful motions, and its ability to sail to windward.

PHYSALIAE
Phy*sa"li*æ, n. pl. Etym: [NL.] (Zoöl.)

Defn: An order of Siphonophora which includes Physalia.

PHYSEMARIA
Phys`e*ma"ri*a, n. pl. Etym: [NL., from Gr. (Zoöl.)

Defn: A group of simple marine organisms, usually classed as the lowest of the sponges. They have inflated hollow bodies.

PHYSETER
Phy*se"ter, n. Etym: [L., fr. Gr. physétère.]

1. (Zoöl.)

Defn: The genus that includes the sperm whale.

2. A filtering machine operated by air pressure.

PHYSIANTHROPY
Phys`i*an"thro*py, n. Etym: [Gr.