432 
VERTEBRATA. 
known species. It inhabits the rivers of the warm parts of America, and feeds on Crustacea. It 
is of small size, and is of little value for food. 
Another family is that of the Polypteridce ; one species, the Polypterus hichir, haunts the 
muddy bottom of the Nile ; it is eighteen inches long, and has sixteen dorsal fins. It is esteemed 
an excellent fish. Another species, P. Senegalus, found in the Senegal, has twelve dorsal fins. 
Of the Lepidosteidce^ the only existing family is that of the Bony Pikes, found in the rivers and 
lakes of the United States. They are of a long pike-like form, the jaws produced into a long 
narrow snout, presenting a resemblance to that of the gavial. Their flesh is generally good. 
Genus LEPIDOSTEUS : Lepidosteus, includes the Buffalo Ray-Pike, L. bison, two to three 
feet long ; found in Lake Erie and other lakes in that region. The Flat-nosed Ray-Fish, L. 
platyrhynckus, is about two feet long, and is found in Florida. There are several other species. 
ORDER 3. TELEOSTEA. 
This extensive and important order derives its name from two Greek words, teleos, complete, 
and osteon, bone, and corresponds nearly with Cuvier's great section of Osseous Pishes. The 
skull is always of a very comj)licated structure, and composed of numerous bones ; the gills are 
supported upon free bony arches, and the water passes away from them by a single opening, 
protected by a bony operculum or gill-cover. The mouth is always formed by a pair of regular 
jaws, and usually armed with teeth. Many are covered with naked skins, but the majority have 
horny scales of various forms. We shall notice them under six divisions, as follows : the Plec- 
tognatha, Lophohranchia, Acanthoptera, Pharyngognatha, Anacanthina, and Pkysostomaia. 
THE PLECTOGlsrATHA. 
This term is compounded of two Greek words, plektos, united, and gnathos, a jaw, and alludes 
to the principal characteristic of the group, the firm attachment of the bones of the upper jaw and 
palate to the cranium. The division includes many species, some of which are of very extraor- 
dinary appearance. Among them are the Trunk-Pishes, of which there are several species, cov- 
ered with an inflexible bony armor. 
THE TRUNK-FISH. THE SEA-PORCUPINE. 
The Dromedary Trunk-Fish, Lactophrys camelinus, three and a half inches long, and Yale's 
Trunk-Fish, L. Yalei, fourteen inches long, are found on our coasts. The Six-horned Trunk- 
Fish, Ostracion sex-cornutus, is found in the Gulf of Mexico. 
To this group also belong the Balis tes, of which there are several species, having a thick, 
leathery skin, often beset with spines. They chiefly inhabit warm climates, but one species, 
the Dusky Balistes, B. fuliginosus, twelve inches long, is found on our coast. There arc also 
several species of this family, belonging to the genus Monocanthus, and called Pile-Fishes, com- 
mon in our seas. They are of various sizes, from four inches to two feet. One of them, the 
Long-finned File-Fish, M. hroccus, eight inches long, is called the Pool-Fish, on account of its 
absurd manner of swimming, with a Avriggling motion, its body being sunk and its mouth on a 
level with, the surface of the water. It is common in New York harbor, and is often taken in 
nets set for other fishes. 
