ACANTHOPTERTGII. 435 



XXVII. Preopercle articulated with the orbit. 

 Head and body more or less angular, cuirassed 

 with plates, or keeled scales covering the 

 body Cataphracti. 



Ninth group. GOBIIFOEMES. 



Spinous dorsal short and composed of flexible spines, the soft dorsal 

 and anal being of equal extent; ventrals, when present, thoracic or 

 jugular, having 1/5 or 1/4. A prominent anal papilla. 



XXVIII. Ventrals either united so as to form a 

 disk or else placed close together ; anal spines 



may be present Gobiidae. 



XXIX. Two dorsal fins, the first with from four 



to six flexible spines ; ventrals wide apart . . Callionymidae. 



Tenth group. BLENNLIFORMES. 



Body elongate and more or less cylindrical. Spinous portion of dorsal 

 fin, when distinct, may be as fully developed as the soft part, or even 

 more so ; anal more or less elongate ; ventrals, if present, thoracic or 

 jugular ; caudal, when present, sometimes subtruncated or rounded. 



XXX. Ventral fins, when present, jugular; anal 

 spines few, or absent. Often a prominent 



anal papilla Blenniidae. 



XXXI. Ventrals jugular. One or two spineless 



dorsal fins; no anal spines; no anal papilla. . Trichonotidae. "**" 



XXXII. Ventrals thoracic, with one spine and 5 

 rays. Body elongate and band-like. A 

 single long dorsal and anal fin, both of soft 



rays Cepolidae. 



XXXIII. Body eel-like. Anterior portion of the 

 dorsal fin consisting of numerous free spines ; 



ventrals absent. No prominent anal papilla. . Rhynchobdellidae. 



Eleventh group. MUGILIFOBMES. 



Two distinct dorsal fins, the anterior short or similar to the posterior; 

 ventrals well developed, abdominal, 1/5. 



XXXIV. Body elongate, subcylindrical. Teeth 

 large and cutting. Lateral line continuous. 



Vertebra 24 Sphyraenidae. 



XXXV. Body more or less elongate and somewhat 

 subcylindrical. Lateral line indistinct. Den- 

 tition feeble or moderate. Vertebrae usually 



exceeding 10/14 Atherinidae. 



XXXVI. Body more or less elongate and some- 

 what subcylindrical. No lateral line. Den- 

 titiou feeble. First dorsal consisting of four 



stiff spines. Vertebrae 24 Mugilidae. 



