34 The Ganoids : 
and essentially to the Cycloganoidet of Gill. The Protospondyli 
(xporos, before; ozovédvdos, vertebra) of Woodward contains 
essentially the same elements. 
Pachycormide.—In the family of Pachycormide the noto- 
chord is persistent, the ethmoids and vomer fused and pro- 
jecting between the maxillaries to form the prominent snout, 
the teeth large, the body fusiform, the dorsal short, with slender 
tays and few fulcra or none, and the scales are thin and rhombic. 
The numerous species are characteristic of the Triassic, Jurassic, 
and Cretaceous. In Sauropsis (longimana) the body. is elon- 
gate, and the pectoral fins are large and sickle-shaped. Luthy- 
notus has small fulcra. In Pachycormus (macropterus, esocinus, 
etc.) the form is robust and the ventral fins are wanting. In 
Hypsycormus ventrals are present, and the caudal deeply forked. 
In the American family of Protosphyrenide the jaws are 
armed with very strong teeth, as in the Barracuda, which, 
however, the species do not resemble in other respects. Proto- 
sphyrena nitida, perniciosa, and numerous other extinct 
forms, some of them of large size, were voracious inhabitants 
of the Cretaceous seas, and are found fossil, especially in North 
Carolina and Kansas. Numerous species called Erisichthe and 
Pelecopterus are all referred by Hay to Protosphyrena. In 
this family the scapula and coracoids are ossified, and perhaps. 
the vertebre also, and, as Dr. Hay has recently suggested, the 
Protosphyrenide may really belong to the J. sospondyli, In any 
event, they stand on the border-line between the most fish-like 
of the Ganoids and the most archaic of the bony fishes. 
The Lrodesmide (genus Liodesmus) are much like Amia, but 
the notochord is persistent, its sheath without ossification. 
Liodesmus gracilis and L. sprattiformis occur in the lithographic 
stones of Bavaria. Woodward places Liodesmus with Megalurus 
among the Amzide. 
The Bowfins: Amiide.—The Amide have the vertebree more 
complete. The dorsal fin is many-rayed and is without distinct 
fulcra. The diamond-shaped enameled scales disappear, giving 
place to cycloid scales, which gradually become thin and mem- 
branous in structure. A median gular plate is developed be- ° 
tween the branchiostegals. The tail is moderately heterocercal, 
and the head covered with a bony coat of mail. 
