Classijication of the Order Pedi'culati'. 285 



and filling tlie interspace between tlic fiontals (fig. 5, A) ; 

 opercles very broad. Vertebr;n l',> ; third to sixth elongate ; 

 praL'Caudals with neural arches huuiiiar, rigidly united, 

 posteriorly (from the seventh) with rather feeble parapo- 

 physes. Two long pectoral radials. 



Principal genera : Oncliocephalus {M(dthe), IJcdteutea, 

 llalleutichtliysj Dihranchus, MallhopsiSj Halicinetus, Ccelo- 

 phri/s. 



Garnian has figured the skeleton of Malthopsis (Mem. 

 ]\lus. Comp. Zool. xxiv. 1899, pi. xxvi.). 



In the typical genera the tail is well-marked off from a 

 strongly depressed circular, ovate, cordate or triangular disc; 

 in Ilalieutella (which may be a young Ilalieutichthys) the 

 disc is subspherical ; in Co'hphrys the form is oblong, as 

 broad as deep, the trunk gradually passing into the tail. 



Like the J.ophiida3, these are shore-fishes or live on tho 

 bottom in deep water. 



Division 3. Ceratiifoemes. 



Pelvic fins absent. Lower j)haryngeals reduced, toothless. 

 Gills complete on second and third arches, absent or reduced 

 to a hemibranch on first and fourth ; no pseudobranchije. 

 Parasplienoid not meeting frontals ; a trough or groove on 

 upper surface of skull, its floor wholly or mainly formed by 

 supraoccipital. Prgecaudal parapophyses directed vertically 

 downwards, free. Pectoral radials comparatively short. 



These are fishes of the open sea, swimming at various 

 depths, uniform in colour, and with the illicium often ter- 

 minating in a luminous bulb. 



Synopsis of the Families. 



I. Illicium present, inserted on upper surface of head ; a single 



nostril on each side. 



A. Anal tin short, few-rayed ; pectorals small. 



1. Soft dorsal short, few-rayed. 



Mouth protractile ; parietals present ; frontals 



united throughout their length ; 3 pectoral 



radials 1. C'eratiidce. 



Mouth not protractile ; parietals absent ; frontals 



separated by the supraoccipital ; 2 pectoral 



radials 2. Hinuuitolophidce. 



2. Soft dorsal longer, of 12 to 15 rays ; mouth not protractile ; 



parietals present ; frontals separated by the supraoccipital ; 

 3 pectoral radials 3, Melanocetidce. 



B. Anal and soft dorsal moderately long, of 11 to 17 r.ays ; pectorals 



large 4. Caulophrynidce. 



II. Illicium inserted at end of snout 5, Giyantactinidce. 



III. Illicium absent ; two nostrils on each side. 6. Aceratiidce. 



