20 



Fig. 3. Melosira distans , (3), valves 4-20u in diameter, 



4-8p long. X 1000. Abundant in southeastern rivers, 



Notes 



girdle view 

 var. lirata, 

 form lacusris 



Fig. h. Melos ira granulata, (3), valves 5-21u in diameter, 

 5-l8|-i long; terminal cells usually with robust 

 spines. X 1000. Common in northern U. S. 





-JTjnr 



:V;Y? 





srrvr. 





girdle view 



valve mantle 



Notes 



Fig. 5. Melosira herzogii , (7), valves 4u in diameter, 7m 



long. X 2000. Found most often in southeastern U.S. 



girdle view 



Notes : 



