CLASSIFICATION 379 



and Cutlass-fishes {Trichiuridae), etc.; the Scombroidea, with the 

 Mackerels, Tunnies, and their alUes {Scombridae) , and the 

 Sword-fishes (Xiphiidae), Spear-fishes and Sail-fishes {Istio- 

 phoridae); the Gobioidea, with the Gobies [Gobiidae) and aUied 

 forms; the Blennioidea, with the Wolf-fishes (Anarrhichadidae), 

 Blennies (Blenniidae), Kelp-fishes (Clinidae), Brotulids (Brotulidae), 

 and other forms; the Stromateoidea, with the Butter-fishes, 

 Rudder-fishes, and Square-tails [Stromateidae) ; the Anabantoidea, 

 including all the Labyrinthic-fishes ; and the Mugiloidea, with 

 the Grey Mullets {Mugilidae), and the Barracudas (Sphyraenidae). 



The Mail-cheeked Fishes, forming the order Scleroparei, 

 represent a large and varied assemblage of fishes, the more 

 generahsed of which are closely related to some of the Perch-Hke 

 forms, but dififer in having a bony "stay" or posteriorly directed 

 process running from a bone below the eye towards the 

 operculum. The Rock Perches or Scorpion-fishes {Scorpaenidae) , 

 Poison-fishes {Synanceidae) , Gurnards {Triglidae), GreenUngs 

 {Hexagrammidae), Sculpins and Bull-heads {Cottidae), Flat-heads 

 \piatycephalidae), Lump Suckers {Cyclopteridae) , and Flying 

 Gurnards {Dactylopteridae) , all belong to this order, and probably 

 also the Sticklebacks (Gasterosteidae) . A small order, the 

 Hypostomides, including the grotesque Dragon-fishes (Pegasidae), 

 may be placed here, although their true systematic position is 

 uncertain. The Remoras, or Discocephali, have been derived 

 from the Percomorphi, differing in having the first dorsal fin 

 transformed into a sucking disc {cf. p. 69) ; and the Flat-fishes, 

 or Heterosomata, have been derived from the same stock {cf. p. 68). 

 Three main groups of Flat-fishes may be recognised, the Psetto- 

 doidea, including the primitive genus Psettodes, the Pleuronectoidea, 

 with the Halibut {Hippo glossus), Plaice {Pleuronectes) , Turbot 

 {Rhombus), etc., and the Soleoidea, with the Soles {Soleidae) and 

 Tongue Soles {Cynoglossidae) . The Plectognathi, another order 

 allied to the Percomorphi, contains the Three-spined-fishes ( Tria- 

 canthidae), File-fishes and Trigger-fishes {Balistidae), Trunk- 

 fishes {Ostraciontidae), Puflfers or Globe-fishes {Tetrodontidae) , 

 Porcupine-fishes {Diodontidae) , and Sun-fishes {Molidae). The 

 small order Malacichthyes, includes only one or two rare fishes 

 whose systematic position is doubtful, and the Cling-fishes, 

 forming the order Xenoptetygii, are clearly modified Percoids. 

 The Haplodoci represent a small order containing the Toad-fishes 

 {Batrachoididae), etc., and this is closely related to the Pediculati, 

 an order which includes the Angler-fishes {Lophiidae), Frog-fishes 



{Antemariidae), Bat-fishes {Ogcocephalidae), and the various 



