EDMONDSON — PROTOZOA OF IOWA. 43 



longer on the ends than on the sides. Aperture plane, or pro- 

 duced into a short trumpet-shaped tube with wavy limb. Monad 

 green, pigment-spot obvious. Flagellum long." 



Length of Iowa forms, 35-40 microns. (Fig. 69, PI. X.) 



Dr. T. C. Palmer, of Pennsylvania, whom I have quoted, discov- 

 ered and described this species. A mature specimen may readily 

 be distinguished from other members of the genus. 



It is an extremely rare form in this state, having so far been 

 found but a few times. Dr. Palmer kindly identified specimens 

 collected by the writer during the summer of 1905. 



Habitat — Found in Iowa among diatoms and other aquatic 

 plants. 



Trachelomonas volvocina Ehr. 



lyorica nearly .spherical, usually brown in color, surface nearly 

 smooth, commonly without a neck. 



Diameter of lorica of large specimen, 30 microns. (Figs. 67-68, 

 PI. IX.) 



Trachelomonas volvocina is the most common species to be 

 observed in this state. The size and the shape of the lorica varies 

 greatly, the spheroidal variety is, however, more numerous. 

 Sometimes loricse, evidently of this species, may be found having 

 short cylindrical necks and in some the tube-like neck may extend 

 inward toward. the protoplasm of the body. Fig. 68, PI. IX, rep- 

 resents a common form, probably of this species. Flagellum 

 long. 



Habitat, fresh water among diatoms, algae and other aquatic 

 plants. 



Trachelomonas hispida Stein. 



lyorica usually elongate-oval with ends broadly rounded. Sur- 

 face covered with minute, sharp pointed spines. Aperture on a 

 level with the anterior border or truncating a short, tube-like 

 neck. Color, some shade of brown. 



This form is widely distributed over the state, being commonly 

 found associated with Trachelomonas volvocina. The species may 

 present a variety of shapes; tho.se most frequently observed in 

 this state, however, are as represented by Fig. 70, Pl.X. 



Large specimens from the locality of Iowa City have reached 

 a length of from 30-36 microns. 



