HACROSEMIIDiE. 
163 
Family MACROSEMIIDJE. 
Trunk elongate or elongate-fusiform, more or less laterally com¬ 
pressed. Cranial and facial bones moderately robust or delicate, 
and opercular apparatus complete; mandibular suspensorium ver¬ 
tical or inclined forwards, and gape of mouth small; marginal teeth 
styliform, inner teeth similar or tubercular. Notochord persistent, 
the vertebrae never advancing beyond the annular stage. Fin-rays 
robust, the majority well-spaced, articulated and divided distally; 
fulcra variable; dorsal fin elongated, usually extending at least half 
the length of the trunk. Scales rhombic. 
The cranial osteology of the Macrosemiidae is as yet very un¬ 
satisfactorily known, the only illustration of importance hitherto 
published being that of the skull of Mcicrosemius by K. A. von 
Zittel, reproduced below (fig. 29). The basicranial axis is always 
straight and nearly parallel with the hinder portion of the cranial 
roof; there is no interorbital septum; the cleft of the mouth is 
horizontal, and the rostrum does not project beyond the mandible. 
Fig. 29. 
Macrosemius latiusculus; head and opercular apparatus, left 
lateral aspect (after Zittel). 
ar., angular; hr., branchiostegal rays; cl., clavicle; d., dentary; hy., cerato- 
hyal ; mx., maxilla ; o., orbit ; op., operculum ; p.op., preoperculum ; 
pa., parietal region ; pi., pterygo-palatine arcade ; pmx., premaxilla 
psph., parasphenoid; qu., quadrate; s.op., suboperculum; spl., splenial; 
vo., vomer. 
In Macrosemius the sclerotic of the eye is ossified, and the cheek- 
plates seem to have been very delicate. The mandibular suspen¬ 
sorium is inclined so much forwards that the articulation of the 
quadrate ( qu .) is beneath the front margin of the orbit (o.). The 
m2 
