678 . FISHES. 



as Murcejia, but tlie former is provided with pectoral fins, and 

 in the latter the posterior nostril is a long slit, and not round 

 as in the other genera. 



FIFTH ORDER— LOPHOBRANCHII 



The gills are not laminated, hut composed of small rounded 

 lobes attached to the branchial arches. Gill-cover reduced to a 



Fig. 308. — Gills of Hippocampus abdominalis. 



large simple plate. Air-bladder simple, without pneumatic 

 duct. A dermal skeleton composed of numerous pieces arranged 

 in segments, replaces more or less soft integuments. Muscular 

 system not much developed. Snout prolonged. Mouth terminal, 

 small, toothless, formed as in Acanthopterygians. 



FiEST Family — Solenostomid^e. 



Gill-openings wide. Two dorsal fins, the rays of the anterior 

 not articulated. All the other fins well developed. 



One living genus only is known, which was preceded in 

 the tertiary epoch by Solenorhynchus (Monte Postale). 



SoLENOSTOMA. — Snout produced into a long tube. Body 

 compressed, with very short tail. All parts covered with thin 

 skin, below which there is a dermal skeleton formed by large 

 star-like ossifications. The soft dorsal and anal fins on elevated 

 bases ; caudal fin long. Ventral fins inserted opposite to the 



