422 ATHEBINIDJS. 



PERCESOCES. 



ATHEKINIDiB. 



Mouth protractile, the maxillaries excluded from the oral border ; teeth in the jaws 

 and on the pharyngeal bones. Body covered with cycloid or ctenoid scales. Praecaudal 

 vertebrae with strong parapophyses, bearing the ribs ; epipleurals inserted on the ribs. 

 Pectoral fins inserted high up ; ventral fins more or less remote from the pectorals, 

 with one spine and five soft rays. Two well-separated dorsal fins, the anterior, if not 

 rudimentary, small and formed, at least in part, of non-articulated or spinous rays. 

 Air-bladder present. 



Although associated with the Acanthopterygians in many classifications, the 

 Atherinidse, as well as their allies the Scombresocidse, are nearly related to the 

 Cyprinodontidse, and truly form a connecting-link between the latter and the 

 Mugilidre. The chief reason why they are placed in a different Suborder from 

 the Haplomi is that a duct between the air-bladder and the digestive canal is absent ; 

 they are Physoclystous, like the Perches and their allies, the Cyprinodonts being 

 Physostomous, like the Pike and Carp. As an example of the difficulty which one 

 may find in allocating some of these fishes to their proper position in the system, 

 Protistius, Cope *, may be mentioned — referred first to the Mugilidae, then to the 

 Cyprinodontidse, it is now placed in the Atherinidae. 



The Atherinidae are carnivorous fishes, mostly marine and of small size, and 

 distributed along the coasts of most tropical and temperate seas ; some marine species 

 enter fresh waters, others are entirely confined to these. 



The silvery lateral band which is present in most members of the family explains 

 the names " Priest " (in allusion to the stole) and " Silver-side " which have been 

 given to them. 



About sixty-five species are known, referred to fifteen genera. 



We have here to deal with only a single species of the genus Atherina. 



* Of. H. W. Fowler, Proc. Ac. Philad. lv. 1904, p. 737, pi. xliv. 



