THE EUGLENOIDINA OF OHIO 343 



THE EUGLENOIDINA OF OHIO 



A Review of the Described Species of the order Euglenoidina 

 Bloch. class Flagellata (Protozoa) with particular reference 

 to those found in the city water supplies and in other locali- 

 ties of Ohio. 



L. B. Walto7i 



1. Introduction. 



(a) GENERAL. 



Among- the minute forms of life frequenting inland waters 

 and in particular, lakes, ponds, reservoirs, and stagnant pools, is 

 an order of single celled organisms belonging to the class Flagel- 

 lata of the Protozoa, the representatives of which possess charac- 

 teristics of both animals and plants. They are not only of in- 

 terest from their economic importance, inasmuch as many of the 

 species at times occur in great numbers and impart peculiar odors, 

 tastes, and colors to water, rendering it unpalatable for drinking 

 purposes, but they are also of much interest from an educational 

 standpoint, since they furnish an extremely valuable type in gen- 

 eral use for biological instruction both in collegiate work and in 

 the laboratory work of the better grades of high schools. 



While the majority of species are sufficiently distinct from 

 one another to permit of recognition, the absence of a satisfactory 

 review has prevented any general knowledge of these small 

 organisms and has also resulted in many errors and inaccuracies 

 of classification even among those biologists who have interested 

 themselves in the forms allied to Euglena. It was largely with 

 a view of attempting to remedy such conditions that the present 

 paper, the outcome of studies during the past ten years, was com- 

 menced. Just as the work was nearing completion, Pascher and 

 Lemmermann's "Die Siisswasserflora Deutschlands, Osterreichs 

 und der Schweiz" (Flagellatae, 1914) was issued. While the 

 tables of genera and species, nearly all completed at that time in 



Contributions from tlie Biological Laboratory of Kenjon College No. 12. 



