1326 
Family HALOSAURIDAE 
Body elongate, long slender tail narrowed into sort 
of filament. Head depressed in front. Snout flattened, 
protrudes beyond mouth. Eye rather large. Mouth horizontal, 
moderate, front edge formed by premaxillary, hind edge by 
maxillary, which moderately wide. Teeth in bands in jaws, 
on rudimentary palatines and tyerygoids, none on vomer and 
tongue. Facial bones with large muciferous cavities. Bones 
of head unarmed. Gill rakers short. Gill membranes free 
from isthmus. Scales cycloid, present on trunk and sides of 
head. No axillary scales. Lateral line low, extends along 
sides of belly, its scales enlarged, each in pouch of black 
skin with luminous organ at base. Dorsal inserted behind 
ventral, before vent. Anal rays about 200. Pectoral long, 
narrow. Ventral moderate. 
Analysis of genera 
Head without prominent lateral ridges; scales 
in lateral line scarcely enlarged. 
Halosiaurus, 
Head with prominent lateral ridges; scales in 
lateral line enlarged, Halosauropsis. 
