652 TELEOSTEI chap. 



Rays of the caudal fin not strongly forked at the base ; ventral fins with one 

 spine and six to eight soft rays, or cranium asymmetrical 



III. Zeorhoiibi. 



II. No suborbital stay ; basis cranii double ; scapula absent, the pterj'gials 

 inserted on the coracoid ; ventral fins thoracic IV. Kurtiformes. 



III. No suborbital stay ; basis cranii simjale ; scapula and coracoid more 

 or less reduced, sometimes vestigial ; pterygials large, only one or two ju 

 contact with the coracoid ; ventral fins thoracic V. Gobiiformes. 



IV. No suljorbital stay ; basis cranii simple ; a perforate scapula ; three 

 pterygials in contact with the coracoid ; ventral fins thoracic ; a suctorial 

 laminated disk on the upper surface of the head . VI. Discocephali. 



V. A suborbital stay, the second suborbital bone more or less produced on 

 the cheek or joining the praeoperculuni ; ventrals thoracic 



VII. SCLEROPAREI. 



VI. No suborbital stay ; ventrals usually jugular or mental ; if thoracic, 

 structure of the pectoral arch differing from that ascribed to tlie first five 

 divisions of this Synopsis. 



Pectoral fin with vertical or subvertical baso ; anal fin usually elongate, 

 rarely small . ...... VIII. Jugulares. 



Pectoral fin with horizontal or sub-horizontal base ; body exceedingly com- 

 pressed ; dorsal fin with all the rays simple ; anal fin absent or very 

 small ....... IX. Taeniosomi. 



Division I.— PERCIFOEMES. 



No bony stay for the praeoperculuni. Basis cranii double. 

 Spinous dorsal usually well developed. None of the epipleural 

 bones attached to the centra of the vertebrae in the praecaudal 

 region. Pectoral arch with well-developed scapula and coracoid, 

 the former pierced by a foramen or fenestra ; pterygials longer 

 than broad, more or less regularly hour-glass-shaped, four or five 

 in number, one or two of which are in contact with the coracoid. 

 Ventral fins thoracic. 



This large group, consisting chiefly of marine forms, has 

 members in all parts of the world, with the exception of the 

 Arctic and Antarctic regions, and was already represented by 

 numerous Berycidae and a few Serranidae and Scorpididae in 

 the Upper Cretaceous. The division into families is a task of 

 considerable difficulty, and the necessities of a linear arrangement 

 result in the breaking up of some natural sequences. Thus it 

 appears highly probable that the Scorpididae, themselves derived, 

 together with the Serranidae, from the Berycidae, lead to the 

 Carangidae in the division Scombriforrnes, whilst a nearly perfect 

 passage can be traced between the Acanthuridae of this division 

 and the Balistidae among the Plectognaths. 



