28 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 124 



analagous to that of Psettodes among the Pleuronectiforrnes (Norman, 

 1934). 



As noted above, Greenwood, et al. (1966, p. 397), have added the 

 ophidioids and zoarcids to the order Gadiformes. In the present paper 

 the more generally held view that the ophidioids and zoarcids (see 

 below) have no close relationship to the gadoid fishes or to one another 

 is supported. In agreement with Makushok (1958 and elsewhere), the 

 zoarcids are assigned herein to the Blennioidei, close to the stichaeid 

 families. The ophidioids differ from these and all blennioids in having, 

 among other things, the dorsal and anal fin rays more numerous than 

 the vertebrae between them and, except in the Carapidae, which lack 

 pelvics, in the one or two rayed filamentous pelvic fins. That the 

 similarity between the zoarcids and ophidioids in ramus lateralis 

 accessorius nerve pattern (Freihofer, 1963) may be the result of 

 convergent evolution has been suggested above. 



Regarding the fin-ray-to-vertebra relationship and the filamentous 

 pelvic fins, some of the gadoids are similar to the ophidioids. Further- 

 more, there seems to be no one well investigated character by which 

 all of the gadoids can be separated from all ophidioids; for example, 

 no pelvic differences can be used to differentiate the two groups 

 because the carapids among the ophidioids and the gadiform genus 

 Macruroides completely lack pelvics. Again, Svetovidov (1948) 

 placed considerable emphasis on the penetration of the intercalar by 

 the glossopharyngeal nerve in gadoids, but this did not occur in the 

 macrurids that Pf tiller (1914, p. 76) investigated. 



Despite the lack of criteria that will separate all gadoids from all 

 ophidioids, I follow Regan (1903b), Svetovidov (194S), and others 

 in separating these two groups widely. If, as I have tried to show, the 

 ophidioids can be traced back through a fish very much like Gadopsis, 

 then the percoid derivation of the ophidioids seems assured; by con- 

 trast, no one in recent years has suggested a percoid derivation for 

 the gadoids (see, e.g., Rosen, 1964; Gosline, 1964). Leaving aside 

 presumed ancestries, however, many of the central tendencies in the 

 two groups are very different. Regan (1903b) noted a number of 

 these tendencies long ago, and more have been added by subsequent 

 authors. 



Suborder Xiphioidei 



The suborder Xiphioidei, as herein understood, comprises the 

 families Istiophoridae, Xiphiidae, and, provisionally, the Luvaridae. 



The Istiophoridae and Xiphiidae usually have been considered "a 

 highly specialized end-stage of the scombriform series" (Gregory and 

 Conrad, 1937, p. 2 3). The Luvaridae, containing only Luvarus 



