The Ganoids 28 
Woodward places these fishes with the Semionotide and Ha- 
lecomorphi in his suborder of Protospondyli. It seems preferable, 
however, to consider them as forming a distinct order. 
Order Lepidostei—We may place, following Eastman’s edition 
of Zittel, the allies and predecessors of the garpike in a single 
order, for which Huxley’s name Lepidostet may well be used. 
In this group the notochord is persistent, and the vertebrz are 
in various degrees of ossification and of different forms. The 
Fic. 13.—Mesturus verrucosus Wagner. Family Pycnodontide. 
(After Woodward.) 
opercles are usually complete, the branchiostegals present, and 
there is often a gular plate. There is no infraclavicle and the 
jaws have sharp teeth. The fins have fulcra, and the supports 
of the fins agree innumber with the rays. The tail is more or less 
sheterocercal. The scales are rhombic, arranged in oblique series, 
‘ which are often united above and below with peg-and-socket 
articulations. This group contains among recent fishes only the 
garpikes (Lepisosteus). They are closely allied to the Palgonts- 
cide, but the skeleton is more highly ossified. On the other 
hand they approach very closely to the ancestors of the bow- 
fin, Amita. One genus, Acentrophorus, appears in the Permian; 
the others are scattered through Mesozoic and Tertiary 
rocks, the isolated group of gars still persisting. In the gars 
the vertebree are concavo-convex, with ball-and-socket joints. 
In the others the vertebrae are incomplete or else double-con- 
cave, as in fishes generally. 
