57. SCOMBERESOCIDiE. 
371 
Order Q -SYNENTOGXATHI. 
[The Synentognathous Fishes.) 
Lower pharyngeal bones fnlly united 5 second and ihird superior pha- 
ryugeals much enlarged, oval, not articulated to the cranium, sending 
processes forwards ; the fourth wanting. Ventral fins abdominal, without 
spine, the rays more than 5. Scapula suspended to the cranium by a 
post-temporal bone, which is slender and furcate. Parietal bone much 
reduced. Supraclavicle not distinct ; no interclavicle. Basis of cranium 
double in front, but without muscular tube. Fins without spines. Air- 
bladder usually large, without pneumatic duct. This order includes 
only the family of Scomheresocidce, and marks the transition from the 
Physostomi to the AcanthopterL Its relations with the Raplomi are very 
intimate, (ffov, together; ev-ro^, within; jaw.) 
{Physostomi j)t. familj Scomberesocidoe Giinther, vi, *233-29^.) 
-Family LVIL— SCOMBERESOCIDiE. 
{The Gar-fishes and Flying fishes.) 
Body oblong or elongate, covered with cycloid scales, which are usu- 
ally deciduous. Lateral line running very low, along the sides of the 
belly. Head more or less scaly, usually with vertical sides. Mouth 
various, the jaws being often prolonged into a beak. Premaxillaries not 
protractile, hinged at base mesially; margin of the uj^per jaw chiefly 
formed by the premaxillaries*; the short maxillaries often entering the 
lateral margin ; maxillary often anchyclosed with the premaxillary ; its 
edge slipping under the front of the preorbital. Dentition various. 
Dorsal fin without spines, inserted on the i)osterior part of the body, 
opposite the anal and usually similar to it. Ventrals abdominal, of sev- 
eral soft rays, usually inserted posteriorly. IS"© adipose fin. Pectoral 
fin inserted high, sometimes used as an organ of flight. Caudal fin 
usually forked, the lower lobe the longer. Vent close in front of anal. 
Xostrils large, double, near the eye. Lower pharjmgeals fully united. 
Gill-membranes not united, free from the isthmus. Pseudobranchim 
hidden, glandular. Gill-rakers various. Gills 4, a slit behind the 
fourth. Air-bladder usually large, sometimes cellular. Intestinal canal 
usually simple, without cceca. Carnivorous. One genus {Zenarchop- 
