DR. GUNTHER ON THE FISHES OF CENTRAL AMERICA, 405 
D. Lake of Managua.—Although the number of species known from this lake is 
small, the forms are quite peculiar; we find here those species of Heros which are 
distinguished by the extraordinary development of the lips, or by incisor-like teeth, 
which render the separation into a distinct genus necessary. The development of 
these Chromides is the more remarkable, as this lake occupies a space which is 
supposed to have been a portion of a marine channel. 
Heros erythrzeus. Heros lobochilus. 
managuensis. | multispinis. 
labiatus. Neetroplus nematopus. 
KE. Lake of Nicaraqua.—Also the fishes of this lake are, with two exceptions, peculiar ; 
like Lake Managua, it appears to have been part of a marine channel. 
Eleotris longiceps. Heros labiatus (Lake of Managua). 
Heros longimanus. Pimelodus nicaraguensis. 
citrinellus, Gambusia nicaraguensis. - 
dovii. | Pecilia dovii (in common with Lake 
nicaraguensis. Amatitlan). 
F. The fresh waters south of the Lakes of Managua and Nicaragua to the Isthmus of 
Darien.—We are obliged, at present, to unite into one province the fish-fauna of Costa — 
Rica, Veragua, Panama, and Darien, as our knowledge of the fishes of Costa Rica and 
also of Veragua is too incomplete to admit of a comparison with those of the more 
southern part of the isthmus. This is the more to be regretted, as a former separation 
of these two parts and of their faunas is, as we have explained above, a matter of great 
probability. The fishes of the Chagres River show a decidedly South-American cha- 
racter. The identity of the freshwater fish-faunas of the Pacific and Atlantic sides is 
here easily explained by the narrowness of the isthmus. 
Mleotrisapictay) eifeere «15,7 ). — — R. Bayano. 
Agonostoma nasutum . . . . . — Panama. — 
MRONULCOMLE a Sk ss be) Be eee — Panama. — 
Herosparma. . ... . . . Chagres. — — 
BROS Ce Swaine. oe as Western Veragua. 
Acara ceruleomaculata . . . . Chagres. — — 
Arius multiradiatus . 2... a oa R. Bayano. 
lurichthys dorsalis . . . . . — Panama. — 
PANAMENSIS se stesyis) = | — Panama. — 
Pimelodus wagneri. . . . .. — Panama. — 
modestus . . . . . . « Chagres. — -- 
Plecostomus, sp. . . . . . = Chagres. -- — 
Chzetostomus aspidolepis. . . . — Veragua. — 
Chetostomus ?cirrhosus . . . . Chagyres. = = 
Borcanaiimi ts? <9 s . = . “Onasres, — — 
