158 PROCEEDINGS OF THE ACADEMY OF [1883. 



One right and two left pharyngeal bones of this species were 

 found by Mr. Wortman in Southern Idaho. It is named for luy 

 friend, the late Mr. B. B. Redding of San Francisco, Vice-President 

 of the California Academy of Sciences. 



Squalius bairdi Cope. SemotUus bairdi Cope, loc. cit., p. 542. 



This species was established on a right pharyngeal bone which 

 supported four teeth in the principal row. My original reference 

 of it to the genus Semotilus, was based on supposition that the 

 left pharyngeal bone would be found to support five teeth in the 

 principal row. This is shown to be the case by such a bone 

 discovered by Mr. Wortman. It belonged 'to a smaller individual 

 than the typical one, and shows the very narrow basis of a 

 probably shorter stj^le than those seen in the other species here 

 mentioned. 

 Squalius arciferus Cope. Oli<iohelus arciferus Cope, loc. cit., p. 541. 



The most robust species, represented by parts of two pharyn- 

 geal bones. 



DIASTICHUS Cope. 

 Proseedings Amer. Philos. Society, 1870, p. 539. 



An entire pharyngeal bone of the typical species of this genus 

 has five teeth in a single series. The opposite bone of another 

 species presents also five teeth, so that the formula is probably 

 5-5. The teeth are compressed and short, and somewhat expanded 

 transversely to the direction of the bone. They display an 

 oblique grinding surface on use. The}^ might then be referred to 

 the genus Leucus, but the apical branch of the bone is much 

 more elongate and is truncate at the extremity. This character 

 is best seen in D. macrodon, where there appears to have been a 

 superior as well as an inferior symphysis. The direction of the 

 tooth series is at right-angles to this apical portion, as in other 

 genera. 

 Diastichus macrodon Cope. Loc. cit., p. 539. 



A specimen of pharyngeal bone, found by M. Wortman, is not 

 more than half the linear dimensions of those obtained by Mr. 

 King from the same part of Idaho. 

 Diastichus parvidens Cope. Loc. cit., p. 540. 



No additional material. 

 Diastichus strangulatus sp. nor. 



"Represented by two pharyngeal bones from Southern Idaho. 



