from nature by the author's own hand, and engraved on 

 stone by Mr. F. Rlxinger, of New York. 



Also, seven wood-cuts, made by Mr. Bernstein, have 

 been placed in the body of this pamphlet. 



Of the orders and families having representatives in 

 this water, there have been only one or two drawings 

 made of each order. 



Of the frequently found alg^e, fractures and single al- 

 gse, {Conferva, Spirogyra, Desmidium, Diatoma, &c.)I 

 have had no drawings made. 



The crustacean Cypris — figure is made after Carl Claus, 

 Prof, ot Zoology in Marburg ; {Beitrcege zur Kenntniss 

 der Ostracoderi), some of the other figures are made su- 

 perficially, representing only the outlines of their bodies. 

 Many of these mentioned beings are only of periodical 

 appearance, and for months may not be seen. 



In closing, let me again urge upon you, my reader, 

 how interesting you may make this study if yOu only 

 wish. All that is required is a small microscope, cost- 

 ing less than forty dollars, and a few other inexpensive 

 implements. 



Hoping that my labor may find a willing echo in your 

 heart, I submit the following. 



Respectfully, 



February, 1872. The Author. 



