PORTUGUESE MAN-OF-WAR. The popu lar name of certain remarkable siphonophores (q.v.) of the genus Physalia. The pneumatophore or float is an oblong. crested bladder, flattened on the lower side, from which are freely pendent the various individuals of the colony. The most notable of these are the long capturing filaments, which are extraordinarily extensible and con tractile, and are very richly supplied with the nettle-cells, so characteristic of cielenterates fqx.). In a specimen the float of which is inches long, these fila ments trail out to a dis tance of fully 20 feet. The batteries of nettle cells are so numerous and so powerful that fishes of considerable size are paralyzed and devoured, the latter process. however, being chiefly performed by other individuals which are specially devoted to the process of digestion. The nettle-cells of an average sized specimen of Physalia are power ful enough to produce great and sometimes se rious discomfort to hu man beings, if they come in contact with the hands or arms: and this is the case with dead specimens picked up from the beach. The
most common Portuguese man-of-war in the western Atlantic is Physalia pelagica, which has the float six or eight inches long and two or three inches high. The float is a bright, iridescent blue, shading in some places into purple, with the lower part and edges red. The individuals of the colony are chiefly red. though various parts are blue. The float contains a gas, possibly air, which seems to he secreted by glan dular epidermal epithelium at its bottom. The gas can be expelled through an air-pore, by which the interior is always in communication with the outside. By contraction of its float. the animal can sink below the surface. to which it rises again during calm weather. Portuguese men-of-war are found chiefly in the warm seas, and in sonic places in the tropics large numbers are blown ashore when the wind has blown landward for an unusual length of time. They are also carried northward in the Gulf Stream. and during the latter part of the summer are often seen off the southern coast of New England.