Families of Tehostean Fishes. L75 



Osphromenidas in the following suborder. Other families, 

 previously included among the Scombriform Acanthoptery- 

 gians, are placed here on the assumption that the loose 

 attachment of the pelvic bones to the clavicles is a primitive 

 character, and not the result of degeneration, such as occurs 

 in some cases among the Acanthopterygians. Although this 

 suborder is perhaps only an artificial association, it must be 

 borne in mind that, notwithstanding the very wide divergence 

 which exists between the first and last families, however 

 dissimilar their members appear to be at first sight, a gradual 

 passage may be traced connecting the most aberrant types. 

 Twelve families : — 



I. Ventral fins, if present, inserted far behind the pectorals; no spines 



to the fins. 



Ribs attached to the extremity of much-developed 

 parapophyses ; lower pharyngeal bones com- 

 pletely united; pectoral fins inserted very 

 high up 1. Scombresucidce. 



Ribs mostly sessile ; lower pharyngeal bones 

 distinct ; pectoral fins nearer the ventral than 

 the dorsal line 2. Ammodytidce. 



II. Ventral fins, if present, more or less approximated to the pectorals. 



A. Two well-developed dorsal fins, the anterior small and form-d, 



at least in part, of spinous rays. 



1. Ribs attached to strong parapophyses. 



Pelvic bones free or connected with the clavicles 



by ligament; pectoral fins inserted high up. . 3. Atherinidce. 



Pelvic bones suspeuded from the postclavicles ; 

 pectoral fins inserted very high up ; teeth very 

 feeble or absent 4. Mugilklce. 



Pelvic bones suspended from the postclavicles; 

 pectoral fins nearer the ventral than the 

 dorsal line, with detached lower rays 5. Polynemidce. 



Pelvic bones connected with the clavicles by liga- 

 ment ; pectoral fins nearer the ventral than 

 the dorsal line ; dentition powerful, cardi- 

 form ; scales minute or absent 6. Chiasmodontidce. 



2. Anterior ribs sessile; pelvic bones not connected with the 



scapular arch ; pectoral fins nearer the ventral than the 

 dorsal line 7. Sphyrcenidce. 



B. Spinous dorsal, if present, connected with the soft. 



1. Anterior vertebrae without parapophyses ; scales on head, if 

 present, small. 



(Esophagus with lateral sacs which are beset with 

 papillae internally ; spinous dorsal long ; 

 scales rhomboidal, in oblique transverse 

 series ; pelvic bones free 8. Tdragonurida. 



