158 ACANTHOPTERYGII. 



Sixth Group Acantkopterygii Gobiiformes. 



No osseous articulation between the suborbital ring of bones and the angle 

 of the preopercle. A single rayed dorsal fin sometimes divided into two parts, 

 the anterior portion of which is composed of spines, which are fewer in number 

 than the rays : soft dorsal and anal generally of equal extent. Ventrals, when 

 present, thoracic or jugular and composed of one spine, and four or five rays. A 

 prominent anal papilla. 



Family, XVII GOBIIDJE, Cuvier. 



Pseudobranchise present, but sometimes rudimentary. Gill openings varying 

 from extremely narrow to wide, the gill-membranes attached to the isthmus: four 

 gills. Body generally elongated. Eyes lateral, occasionally prominent, and mostly 

 without free orbital margins, the skin being continued directly over their surface. 

 No osseous articulation between the suborbital ring of bones and the angle of the 

 preopercle. Teeth of varying characters, mostly small : canines present or absent. 

 A single rayed dorsal fin sometimes divided into two portions, the spines flexible 

 and less in number than the rays : anal similar to the soft dorsal. Ventrals some- 

 times united so as to form a disc, or else they arise close together. Scales and 

 lateral line present or absent. Air-bladder mostly absent.* Pyloric appendages, 

 when present, few. 



This family has been much subdivided by different authors, owing to the great 

 variations observable among the species composing it. An account, however, of 

 these appears hardly necessary in a work relating solely to the British forms. 

 The niajoiity are littoral fishes, the species composing which often appear to have 

 an extensive range. 



The number of British genera which compose the family may be restricted to 

 three. 



1. Gobius. Two dorsal fins: teeth in the upper jaw in several rows of pointed 

 ones : body scaled. 



2. Aphia. Two dorsal fins : teeth in the upper jaw in a single series of long 

 ones : posterior to which are two groups of canines : body scaled. 



3. Grystallogobius. Two dorsal fins : teeth conical and fixed : body scaleless. 



Genus I GoBius,f Artecli. 



Cryptocentrus, Ehr. : Awaous, Val. : Choeturicldhys, Rich. : Gephalogobius, 

 Platygobius, Br achy gobius, Hypogymnogobius, Callogobms, Stenogobius, Actino- 

 gobius, Hemigobius, Ctenogobius, Gentrogobius, Acentro gobius, Porogobius, Ambly- 

 gobius, Odontogobius, Pargobius, Zonogobius, Stigmatogobius, Oxyurichthys, Ambly- 

 chmturichthys, Parachceturichthys, Bleeker : Gallichthys, Cope : Glossogobius, 

 Pomatoschistus, Acant ho gobius, Pucyclogobius, Lepidogobius, Pluuogobius, Synecho- 

 gobius, Gobionellus, Gill : GiUia, Giinther : Gobiopsis, Cyclogobius, Oplopomus, 

 Steind. ; Ghonephorus, Samaragdus, Poey : Gobiichthys, Klunz. 



* Urinary bladder generally large. 



f For the definitions of each of the various named subdivisions of the genus Gobius see my 

 Fishes of India, p. 282. 



