Books by Robert G. Howells
Guide to Texas freshwater muss
Guide to Texas freshwater mussels
Guide to identification of har
Guide to identification of harmful and potentially harmful fishes, shellfishes, and aquatic plants prohibited in Texas
Freshwater mussels of Texas
Annotated list of introduced n
Annotated list of introduced non-native fishes, mollusks, crustaceans, and aquatic plants in Texas waters