316 PROTOZOA 



Butzel, H. M., Jr. 1953. Genetic Studies on Paramecium aurclia. Dis- 

 sertation, Indiana University, Bloomington, Indiana. 



Butzel, H. M., Jr. 1955. Mating type mutations in variety 1 of Para- 

 mecium aurclia, and their bearing upon the problem of mating type 

 determination. Genetics, 40, 321. 



Calkins, G. N. 1919. Uroleptus mobilis Engelm. II. Renewal of vital- 

 ity through conjugation. /. Exptl. ZooJ., 29, 121. 



Calkins, G. N. 1920. III. A study in vitality. /. Exptl. Zool, 31, 287. 



Chen, T. T. 1940. Polyploidy and its origin in Paramecium. /. Heredity, 

 31, 175. 



Chen, T. T. 1946a. Conjugation in Paramecium bursaria. II. Nuclear 

 phenomena in lethal conjugation between varieties. /. Morpkol., 

 79, 125. 



Chen, T. T. 1946b. Varieties and mating types in Paramecium bur- 

 saria. I. New variety and types, from England, Ireland, and Czech- 

 oslovakia. Proc. Natl. Acad. Sci. U.S., 32, 173. 



Chen, T. T. 1956. Varieties and mating types in Paramecium bursaria. 

 II. Variety and mating types found in China. /. Exptl. Zool, 132, 

 255. 



Chen, Y. T. 1944. Mating types in Paramecium caudatum. Am. Nat- 

 uralist, 78, 334. 



Cleveland, L. R. 1950a. Hormone-induced sexual cycles of flagellates. 



II. Gametogenesis, fertilization, and one-division meiosis in Oxy- 

 monas. J. Morphol, 86, 185. 



Cleveland, L. R. 19501). Hormone-induced sexual cycles of flagellates. 



III. Gametogenesis, fertilization, and one-division meiosis in Sac- 

 cinobaculus. J. Morphol., 86, 215. 



Cleveland, L. l\. 1950c. Hormone-induced sexual cycles of flagellates. 



IV. Meiosis after syngamy and before nuclear fusion in Notila. 

 J. Morphol, 87, 317.' 



Cleveland, L. R. 1950d. Hormone-induced sexual cycles of flagellates. 



V. Fertilization in Eucomonympha. ./. Morphol., 87, 349. 

 Cleveland, L. R. 1951a. Hormone-induced sexual cycles of flagellates. 



VI. Gametogenesis, fertilization, meiosis, oocysts, and gametocysts in 

 Leptospironympha. ./. Morphol, 88, L99. 



Cleveland. L. R. 1951b. Hormone-induced sexual cycles of flagellates. 

 Nil. One-division meiosis and autogamy without cell division in 

 ( 'rinympha. J. Morphol, 88. 385. 



Cleveland, L. R. 1952. Hormone-induced sexual cycles of flagellates. 

 \ III. Meiosis in Rhynchonympha in one 1 cytoplasmic and two nu- 

 clear divisions followed by autogamy. /. Morphol, 91, 269. 



