10 U. S. BUKEAU OF FISHERIES 



16. Entosphenus tridentatus (Gairdner). Three-toothed lamprey; Western 



lamprey. 

 Pacific coast of America, from southern California to Unalaska; ascending 



streams even to the headwaters of the Columbia for spawning purposes. 

 Petromyzon tridentatus Gairdner, in Richardson, Fauna Bor.-Amer., 1836, 



293, falls of the Willamette River, Oreg. 

 Petromyzon lividus Girard, Pac. R. R. Surv., X, 1858, Pt. 4, Fishes, 379, 



Willamette River, Oreg. 

 Petroynyzon astori Girard, loc. cit., 380, Astoria, Oreg. 

 Ammocoetes cibarms Girard, loc. cit., 383 (larva). 



17. Entosphenus ciliatus (Ayres). 



Streams of northern California. 



Petromyzon ciliatus Ayres, Proc. Calif. Acad. Nat. Sci., I, 1855, 43, San 



Francisco. 

 Petromyzon epihexodon Gill, Proc. Acad. Nat. Sci. Phila., XIV, 1862, 331, 



Fort Reading, Calif. 



Genus 11. LAMPETRA (Bonnaterre) Gray. Brook lampreys. 



Lampetra Bonnaterre, Enc. Meth., 1788; no paging; no type, used for all. 

 Lampreda Rafinesque, Anal. Nat., 1815, 94 (no species named; no 



description. 

 Pricus Rafinesque, loc. cit. (no species named); no description. 

 Lampetra Gray, Proc. Zool. Soc. Lond., 1851, 236 {Petromyzon fiuvialis L.). 



18. Lampetra ayresii (Giinther). Western lamprey. 



Pacific coast of North America from the Fraser River southward to the 

 Sacramento; very close to L. fluviatilis of Europe. 



Petromyzon plumbeus Ayres, Proc. Calif. Acad. Nat. Sci., I, 1854, 27, 

 San Francisco; name preoccupied. 



Petromyzon ayresii Giinther, Cat., VIII, 1870, 505, San Francisco; sub- 

 stitute for plumbeus Ayres, preoccupied. 



19. Lampetra borealis (Girard). Arctic lamprey. 



Streams of northern Alaska and Kamchatka. 



Petromyzon borealis Girard, Pac. R R. Surv., X, 1858, Pt. 4, Fishes, 377, 



Great Slave Lake; not Ammocoetes borealis Agassiz. 

 Ammocoetes aureus Bean, Proc. U. S. Nat. Mus., IV, 1881, 159. Yukon 



River. 



Genus 12. OKKELBERGIA Creaser and Hubbs. 



Okkelbergia Creaser and Hubbs, Occ. Papers Mus. Zool. Univ. Mich., 

 No. 120, 1922, 8 {Petroynyzon lamotteni LeSueur). 



20. Okkelbergia lamotteni (LeSueur). 



Petroynyzon lamotteni LeSueur, New York Fauna: Fishes, 1842, 382, pL 



79, fig. 249; no locality. 

 AmynocoBtes sepyptera C. C. Abbott, Proc. Acad. Nat. Sci. Phila., XII, 



1860, 327 (type redescribed by Fowler, ibid., 1901, 328; 1907, 466). 



Class III. ELASMOBRANCHII. (Selachii, Plagiostomata, Chondrop- 

 terygii, Antacca). Sharks; Skates and rays; Chimseras 



Subclass SELACHII. Sharks 



Order D. CESTRACIONTES 



Suborder PROARTHRI 



Family 6. HETERODONTID.ffi. Bullhead sharks 



Genus 13. GYROPLEURODUS Gill. 



Gyropleurodus Gill, Proc. Acad. Nat. Sci. Phila., XIV, 1862, 331 and 489 



{Cestracion francisci Girard). 

 Tropidodus Gill, loc. cit., 489 {Cestracion pantherinus Valenciennes = 

 Cestracion quoyi Fr6minville). 



21. Gyropleurodus francisci (Girard). Bullhead shark. 



Coast of California; abundant south of Point Conception. 

 Cestracion francisci Girard, Proc. Acad. Nat. Sci. Phila., VII, 1854, 196, 

 Monterey Bay, Calif. 



