The Ganoids 259 
Woodward places these fishes with the Semtonotide and Ha- 
lecomorpht in his suborder of Protospondylt. It seems preferable, 
however, to consider them as forming a distinct order. 
Order LepidosteicWe 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 vertebre are 
in various degrees of ossification and of different forms. The 
Fig. 196.—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 
heterocercal. 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 (Leptsosteus). 
Family Lepisosteida.—The family of Lepisosteide, constituting 
the suborder Ginglymodi (yiyyAvpos, hinge), is characterized 
especially by the form of the vertebrae. 
These are opisthoccelian, convex in front and concave behind, 
as in reptiles, being connected by ball-and-socket joints. The tail 
is moderately heterocercal, less so than in the Halecomorphi, and 
the body is covered with very hard, diamond-shaped, enameled 
