TELEOSTS. 261 



families, ChromiDjE, from fresh water, Pomacentrid^, marine, in which 

 the nostrils are single. 



The three sub-orders following form a blennoid series which have 

 sprung from a percoid stem. 



Sub-Order 8. Trachinoidea. 



Ventrals thoracic or jugular, nostrils single, dorsal spines few, soft 

 dorsal and anal long, body scaled or naked. This sub-order is best de- 

 veloped in the south temperate zone. In the deep-sea Chiasmodontid.e 

 the body is naked, the mouth very large, and two dorsals are present. The 

 species are noted for their sharp teeth and enormous stomach, swallowing 

 fishes several times their own size. The ,Malaca>!thid.e are represented 

 off our shores by the tile-fish, Lopholatilus, of interesting history. Tra- 

 CHINID,E ; mouth oblique, small conical teeth, lateral line distinct. Trach- 

 iniis, weevers ; Uranoscopus, Dac/yloscopus, star-gazers ; Trachinus appears 

 in the eocene. 



Sub-Order 9. Blennioidea. 



Body naked or with ctenoid or cycloid scales ; ventrals thoracic or 

 jugular, sometimes wanting, the soft rays few in number; dorsal fin long, 

 the spiny rays numerous; anal long; tail homocercal. Blennid^, gill 

 openings normal, teeth not molariform ; Blennius, Gunneltus, Cryptacan- 

 thodes. AnarrhichiD/E, posterior teeth are molariform; Anarrhichas, 

 wolf-fishes. 



Sub-Order 10. Ophidioidea. 



Closely related to the last, but without .spines, except sometimes in the 

 posterior part of the dorsal ; tail diphycercal. The eel-pouts are all marine, 

 and occur in all seas. Zoarcid^, ventral fins never filamentous, some- 

 times wanting. Zoarces. OPHlDllDiE, ventrals slender filaments, a little 

 behind the eye. Ophidium. Fierasferid^, ventrals lacking ; vent at 

 the throat. Several species of Fierasfer live as commensals with pearl 

 oysters or in the cloaca of holothurians. 



Sub-Order ii. Berycoidea. 



Ventrals thoracic, soft rays of pectorals more than 5 ; tail diphycercal ; 

 duct of air-bladder, in some cases at least, persistent; body naked or scaly. 

 The berycoids are an archaic group, the genera Beryx, Platycorinus, Holo- 

 centrnin, etc., appearing in the eocene. The nearest relatives are to be 

 sought in the percoids. The living species are marine, and some belong 

 to the deep seas. Berycid^, no barbels on the chin ; dorsal is single. 

 HoLOCENTRlDiE, two dorsals. MuLLiD^, two dorsals and two chin 

 barbels. Mzilhis, the surmullets ; Upeneus, the goat-fishes. Less certain 

 in its position is the family ZeiDjE which has some berycoid affinities, 

 while it also shows relationships to the squamipinnes. 



