30 The Ganoids 
scales in structure similar to that of the teeth. A number of 
peculiar characters are shown by these fishes, some of them 
having often been regarded as reptilian traits. Notable features 
are the elongate, crocodile-like jaws, the upper the longer, and 
both armed with strong teeth. The mandible is without pre- 
symphysial bone. The fins are small with large fulcra, and 
the scales are nearly uniform in size. 
All the species belong to a single family, Leptsostetde, which 
includes the modern garpikes and their immediate relatives, 
some of which occur in the early Tertiary. These voracious 
fishes are characterized by long and slender cylindrical bodies, 
with enameled scales and mailed heads and heterocercal tail. 
The teeth are sharp and unequal. The skeleton is well ossified, 
and the animal itself is extremely voracious. The vertebre, 
reptile-like, are opisthoccelian, that is, convex in front, concave 
behind, forming ball-and-socket joints. In almost all other 
fishes they are amphiccelian or double-concave, the interspace 
filled with gelatinous substance. The recent species, and per- 
haps all the extinct species also, belong to the single genus 
Lepisosteus (more correctly, but also more recently, spelled 
Lepidosteus). Of existing forms there are not many species, 
three to five at the most, and they swarm in the lakes, bayous, 
and sluggish streams from Lake Champlain to Cuba and along 
the coast to Central America. The best known of the species 
is the long-nosed garpike, Lepisosteus osseus, which is found 
throughout most of the Great Lake region and the Mississippi 
Valley, and in which the long and slender jaws are much longer 
than the rest of the head. The garpike frequents quiet waters 
and is apparently of sleepy habit. It often lies quiet for a long 
time, carried around and around by the eddies. It does not 
readily take the hook and seldom feeds in the aquarium. It 
feeds on crayfishes and small fishes, to which it is exceedingly 
destructive, as its bad reputation indicates. Fishermen every- 
where destroy it without mercy. Its flesh is rank and tough 
and unfit even for dogs. 
In the young garpike the caudal fin appears as a second 
dorsal and anal, the filamentous tip of the tail passing through 
and beyond it. 
The short-nosed garpike, Lepisosteus platystomus, is gener- 
