To this fish (P. chromis) more especially is given the name of “Drum,” from the extraordinary sounds which are produced by it and other allied Sciænoids. These sounds are better expressed by the word drumming than by any other, and are frequently noticed by persons in vessels lying at anchor on the coasts of the United States, where those fishes abound. It is still a matter of uncertainty by what means the “Drum” produces the sounds. Some naturalists believe that it is caused by the clapping together of the pharyngeal teeth, which are very large molar teeth. However, if it be true that the sounds are accompanied by a tremulous motion of the vessel, it seems more probable that they are produced by the fishes beating their tails against the bottom of the vessel in order to get rid of the parasites with which that part of their body is infested. The “Drum” attains to a length of more than four feet, and to a weight exceeding a hundred lbs. Its air-bladder has been figured on p. 146.
Micropogon is closely allied to Pogonias, but has conical pharyngeal teeth. Two species from the western parts of the Atlantic.
Fig. 187.—Pharyngeal bones and teeth of Pogonias chromis. A, Upper; B, Lower pharyngeals.
Umbrina.—Snout convex, with the upper jaw overlapping the lower; a short barbel under the symphysis of the mandible. The first dorsal with nine or ten flexible spines, the anal with one or two. Scales of moderate size.
Fig. 188.—Umbrina nasus, from Panama.
Twenty species are known from the Mediterranean, Atlantic, and Indian Ocean. One well known to the ancients, under the name of Umbra, is the Umbrina cirrhosa of the Mediterranean, the “Umbrine” or “Ombre” of the French, and the “Corvo” of the Italians. It ranges to the Cape of Good Hope, and attains a length of three feet. Also on the coasts of the United States several species occur, as U. alburna, U. nebulosa, etc.
Fig. 189.—Umbrina nasus, from Panama.