SUMMARY. 



In the preceding pages are listed and described twelve orders, 

 twenty-five families, sixty genera, one hundred and four species, and 

 six additional varieties. The following list shows the distribution 

 of these species and varieties among the various families and or- 

 ders. 



There are no definite data concerning two of the species {Ameiu- 

 riis lacustris and Leptops oliraris), but they have, no doubt, been 

 taken in the Mississippi and its tributaries. Where a variety form 

 alone is represented and not the species, the variety is enumerated 

 as a species, but when the typical species and the variety occur, 

 the variety is enumerated as one of the six referred to above. 



CLASS MARSIPOBRAIVCIIII. 



ORDER HTPEROARTII. 



Family PETROMYZONID.^. The Lampieys. 



Genus Ichthyomyzon Girard. 



I. concolor (Kirtland). 

 I. castaneus Girard. 



CLASS PISCES. 



ORDER SELACHOSTOMI. 



Family POLYODONTID^. The Paddle-fishes. 

 Genus Polyodon Lae6pMe. 



P. spatlinla (Walbaum). 



ORDER CHONDROSTEI. 



Family ACIPENSEKID.a;. The Sturgeons. 

 Genus Acipenser Linnseus. 



A. rubicundus Le Sueur. 

 Genus SchapWrhynclius Hectel. 

 S. platorynchus (Rafinesque). 



