EXPLANATIONS AND REFERENCES, 

 PLATE CLXXXIII. 



Figures magnified 250 diameters. 



PAGE. 



Figs. 1, 2. SCYTONEMA CATARACTA, from Rocky Mountain specimens, . 252 



" 3, 4. from Niagara specimens, . 252 



Fig. 5-7. SCYTONEMA CALOTRICHOIDES, three specimens from submerged 



sticks, pond, Brown's Mill, New 

 Jersey, . . . .251 



" 8-10. SCYTONEMA NATANS, frequent in ponds, New Jersey, . 251 



' 11-13. SCYTONEMA NAEGELII, typical forms, , . , 252 



