NO. 1388. ON THE AMMODYTOID FISHES— GILL. 163 



sids. A reexamination of the questions involved and especially com- 

 parison of the anatomical peculiarities of the Ammodytids and the 

 Heraerocoetids are greatly to be desired. Lack of material prevents 

 the writer from entering upon the task. 



The figures of the opened mouth show how distinct the northern 

 Ammodytids are — enough so to warrant recognition of the genera 

 Aiiiinodytes and IlyjM'opJu.s^ suggested by Giinther and admitted by 

 Gill, as well as by Jordan and Evermann. In the typical Amiiiodytts 

 {tohlanus) the intermaxillaries are protrusile and the supramaxillaries 

 have peculiar dentiform tubercles connected with the vomer; in Ilypc- 

 roplus {la/iceolati(^) the intermaxillaries are not protrusile, at least in 

 the old, and the vomer is armed with a pair of teeth which have been 

 confounded with the supramaxillary tubercles of Animodytes. 



As to Cohitojjsis, I am unable to appreciate the reasons for the refer- 

 ence of the genus to the "Percesoces." The ventral tins are said to 

 have ''only about 6 divided rays ^''^ and it has short "dorsal and anal 

 tins similar and directly opposed, close to the caudal." On the evidence 

 presented I should have referred the genus to the neighborhood at least 

 of the Esocidte and Poeciliida?, if not with one of them — the latter if 

 the jaws really do agree. The distinctive characters of the Cohitopddi^ 

 are not evident. There may have been unpresented reasons, however, 

 which led the ver}^ distinguished and able ichthyologists of London to 

 the conceptions they have publishinl. The jaws are not represented 

 in the figure of Cohitopsis acntas published in the Catalogue of the 

 Fossil Fishes in the British Museum (IV, p. 355). 



