The white or unstriped mullets are generally smaller, but otherwise differ little. _Mugil curema_ is the white mullet of tropical America, ranging occasionally northward, and several other species occur in the West Indies and the Mediterranean. The genus _Mugil_ has the eye covered by thick transparent tissue called the adipose eyelid. In _Liza_ the adipose eyelid is wanting. _Liza capito_, the big-headed mullet of the Mediterranean, is a well-known species. Most of the mullets of the south seas belong to the genus _Liza_. _Liza melinoptera_ and _Liza_ _cæruleomaculata_ are common in Samoa. The genus _Querimana_ includes dwarf-mullets, two or three inches long, known as whirligig-mullets. These little fishes gather in small schools and swim round and round on the surface like the whirligig-beetles, or _Gyrinidæ_, their habits being like those of the young mullets; some young mullets having been, in fact, described as species of _Querimana_. The genus _Agonostomus_ includes fresh-water mullets of the mountain rivers of the East and West Indies and Mexico, locally known as trucha, or trout. _Agonostomus nasutus_ of Mexico is the best-known species. [Illustration: FIG. 175.—Joturo or Bobo, _Joturus pichardi_ Poey. Rio Bayano, Panama. ] The Joturo, or Bobo, _Joturus pichardi_, is a very large robust and vigorous mullet which abounds at the foot of waterfalls in the mountain torrents of Cuba, eastern Mexico, and Central America. It is a good food-fish, frequently taken about Jalapa, Havana, and on the Isthmus of Panama. Its lips are very thick and its teeth are broad, serrated, loosely inserted incisors. Fossil mullets are few. _Mugil radobojanus_ is the earliest from the Miocene of Croatia. =The Barracudas: Sphyrænidæ.=—The _Sphyrænidæ_, or barracudas, differ from the mullets in the presence of very strong teeth in the bones of the large mouth. The lateral line is also developed, there is no gizzard, and there are numerous minor modifications connected with the food and habits. The species are long, slender swift fishes, powerful in swimming and voracious to the last degree. Some of the species reach a length of six feet or more, and these are almost as dangerous to bathers as sharks would be. The long, knife-like teeth render them very destructive to nets. The numerous species are placed in the single genus _Sphyræna_, and some of them are found in all warm seas, where they feed freely on all smaller fishes, their habits in the sea being much like those of the pike in the lakes. The flesh is firm, delicate, and excellent in flavor. In the larger species, especially in the West Indies, it may be difficult of digestion and sometimes causes serious illness, or "ichthyosism." [Illustration: FIG. 176.—Barracuda, _Sphyræna barracuda_ Walbaum. Florida. ]