The black bass is now introduced into the streams of Europe and California. There is little danger that it will work injury to the trout, for the black bass prefers limestone streams, and the trout rarely does well in waters which do not flow over granite rock or else glacial gravel. The large-mouth black bass (_Micropterus salmoides_) is very much like the other in appearance. The mouth is larger, in the adult cleft beyond the eye; the scales are larger, and in the young there is always a broad black stripe along the sides and no cross-bands. The two are found in the same region, but almost never in the same waters, for the large-mouth bass is a fish of the lakes, ponds, and bayous, always avoiding the swift currents. The young like to hide among weeds or beneath lily-pads. From its preference for sluggish waters, its range extends farther to the southward, as far as the Mexican State of Tamaulipas. _Plioplarchus_ is a genus of fossil sunfishes from the Eocene of South Dakota and Oregon. _Plioplarchus sexspinosus_, _septemspinosus_, and _whitei_ are imperfectly known species. =The Saleles: Kuhliidæ.=—Much like the sunfishes in anatomy, though more like the white perch in appearance and habit, are the members of the little family of _Kuhliidæ_. These are active silvery perches of the tropical seas, ponds, and river-mouths, especially abundant in Polynesia. _Kuhlia malo_ is the aholehole of the Hawaiians, a silvery fish living in great numbers in brackish waters. _Kuhlia rupestris_, the salele of the Samoan rivers, is a large swift fish of the rock pools, in form, color, and habits remarkably like the black bass. It is silvery bronze in hue, everywhere mottled with olive-green. The sesele, _Kuhlia marginata_, lives with it in the rivers, but is less abundant. The saboti, _Kuhlia tæniura_, a large silvery fish with cross-bands on the caudal fin, lives about lava-rooks in Polynesia from the Galapagos to Samoa and the East Indies, never entering rivers. Still other species are found in the rock pools and streams of Japan and southward. The skeleton in _Kuhlia_ is essentially like that of the black bass, and Dr. Boulenger places the genus with the _Centrarchidæ_.