ON THE SYSTEMATIC RELATIONS OF THE AMMODYTOID 



FISHES. 



By Theodork Gill, 



Honorary Associate in Zoology. 



There are few fishes respecting whose affinities there has been so 

 much diversit}" of opinion, especially in later years, as the Sand Launces 

 or Amniodytids. By Artedi, the genus embracing them {Anmiodytes) 

 was referred next to Coryphs&na^ and by Linnaeus it was naturally 

 placed in the unnatural order of Apodes, no v^entral fins being devel- 

 oped. For the same reason it was referred by later ichthyologists 

 who adopted families to the same family as other apodal fishes with 

 long dorsal and anal fins. By all except Bonaparte, during the first 

 half of the nineteenth century, it was associated with OpJdd'iurn in the 

 same family. 



In 18-1:6 Bonaparte first separated the genus from the family of 

 Ophidiids, but retained it near that group. 



In 1861 Gill adopted the family under the name Aininodytoldce.^ 

 modifying the name in accordance with the principle promulgated by 

 Agassiz, who insisted that all family names derived from the Greek 

 should have the termination "-oidte."" The family was removed from 

 association with the " Ophidloidx'''' and placed next after AtJierinoldx, 

 which succeeded ^fugiloidse and Polynematoldx. Subsequently (1872) 

 he reverted to the current views, approximating it to the Ophidiids, but 

 isolating it as the representative of a distinct superfamily — Ammo- 

 dyfo/dea. 



In 1896 Jordan and Evermann (p. 832) isolated the Ammodytidse as 

 a "group Ammodytoidei'''' after the Sphyvpenidx and PolynemidR' and 

 before the Berycoldei., adding that the group " is of unknown rela- 

 tions.'' " In the character of the mouth and gill structures it resembles 



Proceedings U. S. National Museum, Vol. XXVIII— No. 1388. 



159 



