152 



D. H. WENRICH. 



Euglenamorpha hegneri, new species. Since there are two 

 strikingly different although intergrading varieties, it seems de- 

 sirable to establish the green, three-flagellated kind which Hegner 

 discovered as the type variety and to regard the other one as a 

 variation. 



Type form. Diagnosis : Euglenamorpha with body, when elon- 

 gated, generally cylindrical to cigar-shaped, tapering more at the 

 posterior than at the anterior end. Length, 30 to 55 microns, with 

 an average of about 45 microns. Width, 4 to 8 microns, with an 

 average of 5.5 microns. Green chloroplasts, paramylon granules, 

 and red stigma present. The three equal-length flagella are from 

 one-half to two-thirds the length of the body and each has a 

 spindle-shaped swelling on its root in the reservoir adjacent to the 

 stigma. Nucleus, generally compact so as to obscure the caryo- 

 some, commonly placed laterally near the middle of the body. Sur- 

 face striae fine, numerous, and usually spirally arranged passing 

 from the left over to the right. Habitat, rectum of tadpoles. 



Variety pellucida. This variety has the body elongately conical, 

 widest a little behind the reservoir, tapering from there gradually 

 to a sharp posterior tip and more abruptly to the rounded anterior 

 end. Size, similar to the type variety, but averaging a little smaller. 

 Colorless or slightly greenish. Flagella mostly four or six, some- 

 times two, three or five, with no swellings on the roots. Reservoir 

 enlarged, nucleus expanded to width of the body, caryosome con- 

 spicuous and often multiple. Surface strise prominent to absent, 

 generally spirally arranged passing from the right over to the left, 

 although they may have the reverse arrangement or lie parallel 

 with the long axis. Habitat, rectum of ta*dpoles. 



B. The Two Varieties Compared. 



When the two different varieties were first recognized their dif- 

 ferences were so striking that it was thought that they should go 

 into different species if not into different genera, but further study 

 makes it highly probable that the green (type) form transforms 

 into the colorless (pellucida} one. When typical individuals of 

 the two varieties are compared they are found to differ in almost 

 every detail. 



