Families of Tehostean Fishes. 169 



Fourteen families : — 



I. Parietals separating the frontals from the supraoccipital ; post- 



temporal simple; prcecaudal vertebra) with autogenous para- 

 pophyses. 

 Margin of the upper jaw formed by the prse- 

 maxillaries and the maxillaries ; basis cranii 



simple ; no adipose dorsal tin 1 , Galaxiidcc. 



Margin of the upper jaw formed by the prae- 

 maxillaries only ; basis cranii double ; 

 adipose dorsal fin present 2. HaphcMtonidce. 



II. Frontals in contact with the supraoccipital. 



A. Prsecaudal vertebra? without parapophyses. 



1. Margin of the upper jaw formed by the prsemaxillaries and the 



maxillaries. 

 Body without or with minute scales, usually 



with rows of scutes ; adipose dorsal tin 



usually present 3. Encltodontidce f . 



Body scaly ; post-temporal forked ; no adipose 



dorsal tin ; ventrals with 6 to 11 rays .... 4. Esocidce. 

 Bod}' scaly; post-temporal incompletely ossified ; 



pectoral fin without pterygials ; no adipose 



dorsal fin ; ventrals with 3 rays only 5. Dalliidce. 



2. Maxillaries excluded from the oral border. 



a. Adipose dorsal fin usually present ; ventral fin with 7 to 10 



rays. 



Post-temporal forked ; dorsal fin formed of arti- 

 culated rays 6. Scopelida. 



Post-temporal simple ; dorsal fin very long, 

 formed of slender, non-articulated, simple or 

 bifid rays 7. Alepidosauridce. 



b. No adipose dorsal fin ; head and mouth enormous, dentition 



feeble ; body naked ; ventral fins, if present, with 5 rays. 



8. Cetomimidee. 



B. Prsecaudal vertebra? with well-developed parapophyses ; maxil- 



laries excluded from the oral border. 



1. Dorsal and anal fins without spines; scales cycloid, or with 



erect spines ; no adipose dorsal fin. 



Mouth not protractile ; ventral fins far forward, 



with 7 to 17 rays 9. 'Chirothricidee f. 



Mouth not protractile ; ventral fins remote from 



the pectorals, with 9 rays 10. Kneriidce. 



Mouth protractile ; ventral fins, if present, with 



5 to 7 rays 11. Oyprinodontidce, 



Mouth scarcely protractile; ventral fins rudi- 

 mentary or absent ; vent close to the gills. . 12. Amblyopsidce. 



Mouth slightly protractile ; ventral fins with 5 



or G rays 13. Stephanoben/cidai. 



2. Dorsal and anal fins with true spines ; scales ctenoid ; an adipose 



dorsal fin ; ventral fins with 9 rays. , 14. Percop$id<e . 



