161 



144. LITHOLEPIS Rafiuesque, 1818. 

 (syn. Atraerosteus Raf., 1820.) 

 C49. L. adamautinus Raf. Lower Mississippi. 



POLIODONTIDAE. 



145. POLTODON Lacepede, 1798. 

 650. P. folium Lac. Mississippi Valley. 



ACIPEXSEllIDAE. 



146. ACIPENSER Linnaeus, 1748. 

 Type: A. sturio L. marine. 



C51. A. rnbicnndus Le S. Great Lakes and Western Rivera. 



G52. A. maculosus Le S. Ohio River and Great Lakes. 



053. A. transmontanus Rich. Columbia River. 



654. A. rupertiauus Rich. British America. 



147. *SCAPHIRHTNCHOPS Gill, 187-. 



(syn. ScatMrhyncJiua Heckel, 1835 ; preocupied.) 



655. S. platyiiiynchus (Raf.) Cope. Mississippi Valley and S. W. 



PETROMIZOXTIDAE. 



14S. PETROMYZON Linnaeus, 1766. 



Type: P. marinus L. (Europe.) 



656. P. nigricans Le S. Eastern streams and Coast. 



657. P. uiarer Raf. Upper Great Lakes to Ohio Valley. 

 65S. P. tridentatus Gairdner. California and North. 



659. P. liridus Girard. Oregon. 



660. P. borealis Grd. Great Slave Lake. 



661. P. hirudo (Grd.) Nelson. Lake Erie to Arkansas. 



662. P. argeuteus Kirtland. Great Lakes, Ohio Valley. 



663. P. castaneus (Grd.) J. and C. Minnesota. 



* Scaphirhychops Gill, MSS. This name was proposed in manuscript by Prof. Gill some 

 years ago as a substitute for Scaphirhynchus Heckel, preocupied in Ornithology. Scaphirhyn- 

 chops has l}een emploj'ed by several authors, but thus far without explanation. 



BL-L. BUF. SOC. NAT. SCI. (21) DECEMBER, 18~6. 



