1883.] NATURAL SCIENCES OF PHILADELPHIA. 293 



small. Pectorals short, 3 in body, reaching somewhat past front 

 of second dorsal. 



Pectorals and tip of caudal diisk3\ 



30. Agonus decagonus B och. 



This species has the gill membranes attached to the isthmus, 

 forming a narrow fold across it, much as in ^4. cataphractus^ but 

 narrower. It is therefore erroneously referred by us to the genus 

 Brachyopsis (Syn. Fish. N. A., 955 \ and the generic name Lepta- 

 gonus Gill, based on A. decagonus, cannot be used instead of 

 Brachyopsis. A. decagonus is intermediate between Agonus 

 proper and Podothecus, being referable to the latter, if the two 

 genera are kept separate. According to Dr. Liitken, neither 

 Agonus cataphractus nor Coitus biibalis have yet been actually 

 found in Greenland. Thej- should, therefore, be omitted from 

 American faunal lists. 



.31. Ophidium omostigma .lordan & (Jilhert. 



{Genyptenis omostigma Jor. & Gilb., Pvoc. U. S. Nat. Mus , 1883, 

 301.) 



An Ophidioid fish has been referred by us to the genus Genyp- 

 terus, which genus we have regarded as distinguished from 

 Ophidium chiefl}' by the presence of a sharp spine on the opercle. 

 In the t3'pe of the genus Genypternis (G. cMlensis Guichenot), 

 this spine is obsolete. G. omistigma is therefore not a Genypterus, 

 and it may probabl}' be referred to Ophidium, from which Gcnyp- 

 terus is separated by Dr. Giinther on the variable and perhaps 

 unimportant character of the enlarged palatine teeth. 



