7O2 TELEOSTEI CHAP. 



wing-like portion of the pectoral fins, by which they are able 

 to move in the air like Exocoetus, but for shorter distances, and, 

 unlike them, the wings are moved rapidly, the mode of flight 

 resembling that of many forms of grasshoppers ; l the young, 

 however, have comparatively short pectorals, and were formerly 

 regarded as belonging to a distinct genus (Cephalacanthus). 



DIVISION VIIL JUGULAEES. 



No bony stay for the praeoperculum. Ventral fins jugular 

 or mental. Gill-openings in front of the pectoral fin, the base 

 of which is vertical or subvertical. 



In a recently published note 2 I have alluded to the group of 

 Physoclistous fishes for which I proposed to revive the old name 

 Jugulares, pointing out that some of the forms previously 

 grouped together as Trachinidae agree with the Gadidae, not 

 only in the jugular position of the ventral fins, but also in the 

 condition of the scapula and coracoid. Mr. Regan 3 has since 

 been able to show that the Gadidae and Macruridae possess 

 certain characters in common by which they may be separated 

 not only from the other Jugulares, but even from the Acantho- 

 pterygians, and, as mentioned above (p. 646), the Miillerian 

 Sub-order Anacanthini may be maintained, after excluding the 

 Pleuronectidae. That the Blenniidae are akin to Lycodes and 

 its allies has long been admitted, and authors who have placed 

 them in different divisions of their systems have had to confess 

 the difficulty of referring certain genera to the one family rather 

 than to the other. The fact that Lycodes and many forms 

 previously associated with the Ophidiidae agree with the 

 Macruridae and Gadidae in the diphycercal vertebral column 

 and in the absence of spines to the fins is merely, it seems to me, 

 the result of degradation ; they probably form the terminal 

 group of a series in which the vertebral column was originally 

 homocercal and fin-spines were present', as is the case in most of 

 the Blenniidae and Trachinidae and their near allies. All these 

 families may be assumed to have evolved in several series, often 

 on parallel lines, from some group closely related to the 



1 Moseley, Notes Natur. Challenger, 2nd edition, p. 495. 



2 Ann. Mag. Nat. Hist. (7) viii. 1901, p. 261. 



3 Op. cit. xi. 1903, p. 460. 



