28S On the Classification of the Order Pediculati. 



B. No barbel. 



1. Skin without scutes Dolopichthys, Garm., 1899. 



2. Skin with large spinate scutes. 



Form compressed Himantolophus, Reinh., 1837. 



Form depressed Aetjeoaichthys, Clarke, 1878 *. 



Family 3. Melanocetidae. 



Mouth tiot protractile, vertical, wide ; teeth in jaws 

 acicular, depressible; vomer sometimes toothed. Gills 2|. 

 Spinous dorsal represented by a supra-rostral illicium witii 

 terminal bulb ; soft dorsal posterior, moderately long, of 

 12 to 15 rays ; anal short, 4-rayed ; pectorals small. Fra^- 

 inaxillary pedicels short ; maxillaries slender ; skull short 

 and broad, with a large trough superiorly, the floor mainly 

 formed by the large supraoccipital, which extends forward 

 to the ethmoid region ; frontals completely separated 

 (fig. G, C) ; sphenotic not bearing a spine ; opercles narrow. 

 Three pectoral radials. 



Genera : Melanocetus, Liocetus. 



Family 4. Caulophrynidae. 



Mouth not protractile, wide, moderately oblique : teeth 

 acicular, in jaws and on palate. Gills ^ + 2^. Illicium 

 slender, with terminal bulb, inserted on upper surface of 

 head; soft dorsal and anal rather long, of 11 to 16 rays, 

 which are considerably produced ; pectorals large and broad- 

 based. 



This family includes a single genus, Caulophryne, with 

 2 species, C. jordani, Goode & 13ean, and C. pelagiciis, 

 Brauer. Probably the opercles are broader and the jjcctoral 

 radials longer than in other Ceratiiformes. 



Family 5. Gigantactinidae. 

 Oigantactis vanlioeffeni, Brauer, 1902, differs from the 

 Ccratiida} and llimantolophidje in the insertion of the 

 illicium at the extremity of the snout. 



Family 6. Aceratiidae. 

 Mouth terminal, horizontal; 3 rostral denticles (? prae- 

 maxillary teeth) above middle of upper jaw; eyes directed 

 forward; 2 nostrils on each side. Illicium absent; soft 

 dorsal and anal very small, 2- or 3-rayed. 



* This genus may not be distinct from Hiiiuintolophus, as a fish 

 said to be specifically identical with II. reiuhardtii has recently been 

 described and tigured as broader than deep (Williamson, Kep. Fishery 

 Board for Scotland, 1909 (1911), pt. 3, p. 51). 



