ISO ROBERT W. HEGNER. 



that active trophozoites from the latter can be transferred to 

 tadpoles of the green frog with their food. 



(9) It is evident that euglenoids of Species A are regular in- 

 habitants of the intestine and rectum of three species of tadpoles, 

 Rana pipiens, R. clamitans, and Bufo hntiginosus americanus, 

 and that they can be transferred from tadpoles of one species to 

 those of another with the food. No specific differences were 

 noted in specimens from different species of tadpoles. 



(10) Euglenoids of Species B were present in tadpoles of Rana 

 pipiens and R. clamitans, but w r ere never very numerous. The 

 intestine seemed to be more highly infected than the rectum. The 

 specimens observed were as green as free-living species and con- 

 tained brightly colored stigmas. Most of them appeared to be 

 without flagella and either remained stationary except for meta- 

 bolic movements or squirmed slowly from place to place. At- 

 tempts to increase the number present in one tadpole by feeding 

 it infected intestines and recta of other tadpoles were not defi- 

 nitely successful. 



(n) A species of Phacus resembling P. phuronectes was ob- 

 served in a few tadpoles of Rana pipiens. 



(12) The presence of euglenoids had no apparent effect on 

 other protozoan inhabitants of the digestive tract except in the 

 case of certain opalinids which became yellowish green in color. 



The advantages of the group of organisms dealt with in this 

 paper as material for a study of the evolution of parasitism is 

 obvious and the writer expects to continue work on the group 

 with this object in view. 



. LITERATURE CITED. 

 Alexeieff, A. 



'12 Le parasitisme des Eugleniens et la phylogenie des Sporozoaires sensu 

 stricto. Arch. Zool. Exper. et Gen., 5 ser., Notes et Revue, T. 10: 73-88. 

 Haswell, W. A. 



'07 Parasitic Euglenee. Zool. Anz., 31: 296-297. 

 Hegner, R. W. 



'23 Infection Experiments with Euglenoidina Living in the Digestive Tract of 



Frog and Toad Tadpoles. Amer. Jour. Hyg. 3: 97-98. 

 Nieschultz, O. 



'22 Ueber eine Astasia Art aus dem Susswassernematoden, Nilopus gracilis 



Bt., Zool. Anz., 54: 136. 

 Walton, L. B. 



'15 A Review of the Described Species of the Order Euglenoidina Bloch. Ohio 



State Univ. Bull. 19: 341-459. 

 Wenrich, D. H. 



'23 Variations in Euglenamorpha hegneri, n. g., n. sp., from the intestine of 

 Tadpoles. Anat. Rec. 24: 370-371. 



