294 FEESH- WATER KHE30P0DS OF NOETH AMEEICA. 



CONCLUDING REMARKS. 



In closing my observations on the Fresh-water Rhizopods, the results 

 of which are now presented to the world, I am impelled to say that they 

 are neither so complete nor so accurate as it was my desire they should be. 

 At one time I was disposed to lay both manuscript and drawings aside, 

 andxmce more go over the ground before making my researches public. 

 It was only after several years of experience that I felt qualified to investi- 

 gate the subject in the manner it merits and as I should wish to introduce 

 it to the reader. But, taking into consideration the uncertainty of events, 

 and the probability that I might not be able to obtain and investigate the 

 same or similar materials under equally favorable circumstances, or have an 

 equally favorable opportunity for publication, I concluded to send forth 

 the results of my labors, imperfect as they may be. The novel things of 

 the work must compensate for any deficiencies, and the experiences related 

 will prove of assistance to students who may follow in the same path of 

 investigation. I may perhaps continue in the same field of research and 

 give to the reader further results, but cannot promise to do so ; for though 

 the subject has proved to me an unceasing source of pleasure, I see before 

 me so many wonderful things in other fields that a strong impulse disposes 

 me to leap the hedges to examine them. 



The objects of my work have appeared to me so beautiful, as 

 represented in the accompanying illustrations, and so interesting, as indi- 

 cated in their history, which forms the accompanying text, that I am led 

 to hope the work may prove to be an incentive, especially to my young 

 countrymen, to enter into similar pursuits. The study of natural history 

 in the leisure of my life, since I was fourteen years of age, has been to me 

 a constant source of happiness, and my experience of it is such that, inde- 

 pendently of its higher merits, I warmly recommend it as a pastime, than 

 which, I believe, no other can excel it. At the same time, in observing the 

 modes of life of those around me, it has been a matter of unceasing regret 

 that so few, so very few, people give attention to intellectual pursuits of 

 any kind. In the incessant and necessaiy struggle for bread, we repeatedly 

 hear the expression that "man shall not live by bread alone," and yet it 



