FISHES OF FAMILY BLENNHDAE 65 



to greatly excavated; bases of comblike teeth of premaxillaries and 

 dentaries usually not closely and tightly joined to bone (usually 

 loosely suspended in thick band of connective tissue); replacement 

 teeth developing in excavated area of premaxillaries and dentaries 

 (not completely surrounded by bone of jaws); posterior canines 

 present or absent on dentaries (enlarged or normal relative to comb- 

 like teeth), absent on premaxillaries; teeth on premaxillaries 30-250 

 (more than 100 in most genera); ascending process of premaxillary 

 weakly based on body of premaxillary; dentaries united by even, 

 nonsuturing joint; circumorbitals 5 (4 in two genera); supraclei thrum 

 with or without tube for sensory canal. 



Subfamily Nemophidinae. — Basisphenoid absent; intercalar ab- 

 sent (except Dasson) ; pterosphenoid visible or not visible when skull 

 is viewed laterally; ascending process of premaxillary arising broadly 

 and firmly from body of premaxillary; dentaries united by suturing 

 joint (except possibly Runula laudandus) ; premaxillaries and dentaries 

 strong, not excavated; bases of comblike teeth of dentaries and pre- 

 maxillaries closely and loosely to tightly joined to bone; replacement 

 teeth developing internally in hollow of premaxillaries and dentaries 

 (developing replacement teeth completely surrounded by bone of 

 jaws); dentary with greatly enlarged canine posteriorly; vomer with- 

 out teeth (except possibly Plagiotremus spilistius); frontals with or 

 without dense ornamentation (consisting of small to large depressions) ; 

 circumorbitals 3 or 4 ; posttemporal without ventrally extending arm ; 

 supracleithrum articulating anteriorly with epiotic and post-temporal; 

 supracleithrum without tube for sensory canal; last dorsal spine nor- 

 mal; dorsal fin without a notch between spinous and rayed portions; 

 segmented dorsal fin rays 15-119 (more than 24 in most genera); 

 1-4 proximal dorsal fin pterygiophores dorsal to supraoccipital; last 

 anal pterygiophore supporting a single ray; segmented caudal rays 

 10-11; caudal fin without branched rays; pelvic rays, when not de- 

 formed (a common occurrence in some genera), 1,3 (no pel vies in 

 Plagiotremus spilistius); vertebrae 31-134; precaudal vertebrae 11-16; 

 first and/or second neural arch usually incomplete (open above); 

 posteriormost pleural on vertebra 12-16; minimal hypural (hypural 

 5) absent; 1 epural (infrequently 2); gill opening usually restricted to 

 small opening dorsal to level of pectoral base; adults free-swimming 

 during much of their activity. 



Norman (1943) used two characters not included above to distin- 

 guish those genera I include in the Nemophidinae from the other 

 blenniids: the fact that the interorbital width is greater than the 

 orbital diameter; and the natm-e of the relationship of the premax- 

 illaries, median ethmoid, nasals, "praeorbitals" and "postorbitals." 

 The first character does separate some genera of the Nemophidinae 



