Jordan and Evermann. Fishes of North America. 531 



reunited with the Isospondyli or otherwise distributed when the osteol- 

 ogy of the different families is known. In but few genera has the 

 mesocoracoid or the post-temporal received examination. (Iviov, nape ; 

 wtfof, shoulder.) 



Giinther divides the Iniomi into two families, Stomiatidce, and Sternopty- 

 chida 1 , according to the relation of the maxillary to the border of the 

 mouth. Goode and Bean follow Gill in separating the group into many 

 families. Liitken, who has made most valuable studies among the deep- 

 sea forms, seems inclined to recognize several families. He regards it as 

 necessary either freely to subdivide the group or else to regard the whole 

 as a single family. The composition of the group and the varied relations 

 of its parts are best seen by regarding its principal types as of family 

 value. We begin the series with the family which contains most shore 

 species, and which is apparently nearest the Isospondyli, from which group 

 the Iniomi have apparently been modified or degraded. 



Families* of INIOMI. 



a. Post-temporal connected with back of cranium near sides; no photophores or barbel. 



b. Adipose 'fin typically present (rarely atrophied or lost); body not very elongate; anal 



fin distinct. 



c. Scales present, usually persistent; teeth cardiform or villiform, usually movable. 

 d. Maxillary very narrow, rudimentary, or obsolete; hypocoracoids not divergent; 

 pseudobranchise present. SYNODONTID^E, ixvm. 



dd. Maxillary well developed, dilated behind. 



e. Pseudobranchiae present; pectorals normal; hypocoracoids mostly diver- 

 gent, undivided. AULOPIIXE, LXIX. 

 ee. Pseudobranchife absent; pectorals not normal. 



/. Pectorals subhumeral. BENTHOSAURID*:, LXX. 



ff. Pectoral rays elongate, arranged in two groups. 



BATHYPTEROID^E, LXXI. 

 66. Adipose fin absent. 



g. Body covered with scales which are large, thin, and deciduous; teth villiform, in 

 bands; no photophores on the scales, but a large, luminous plate on the head 

 in place of eyes; maxillary dilated behind; pectorals and ventrals well devel- 

 oped, approximate. IPNOPID^E, LXXII. 

 gg. Body scaleless; teeth granular, in bands; pectorals normal. 



h. Ventrals present; opercular apparatus incomplete. RONDELETIIDJE, LXXIII. 

 hh. Ventrals absent; opercular apparatus complete; a conspicuous lateral furrow; 

 general form and appearance of young cetaceans. CETOMIMID^S, LXXIV. 

 aa. Post-temporal impinging upon occiput. 



i. Vertebra) and neural spines normal, not projecting from the flesh in front of the dorsal 



fin. 



j. Photophores present. 

 k. Barbel wanting. 



/. Pseudobranchife present. 



m. Premaxillaries forming entire margin of upper jaw; body scaly; 



opercles complete. MYCTOPHID.*:, i.xxv. 



mm. Premaxillaries not forming the whole margin of upper jaw, the 



maxillary entering into it; body naked; opercular apparatus 



incomplete. MAUROLICID^:, LXXVI. 



II. Pseud obranchite absent; mouth large, with canine teeth; scales deciduous 



or wanting. CHATJLIODONTID^E, LXXVII. 



H: Barbel present, very long. 



*The analysis of the families of Iniomi is chiefly taken from Goode & Bean, Oceanic 

 Ichthyology. 



