48 
Psyche 
[June 
the Milnesiidae and Macrobiotidae (de Barros 1939). In a few 
words, these three genera blur the distinctions that, thirty years ago, 
provided the Tardigrada with a clean-cut suprageneric classification. 
Literature Cited 
de Barros, R. 
1939. ltaquascon umbeilinae gen. nov. spec. nov. (Tardigrada, Macro- 
biotidae). Zool. Anz. 128: 106-109. 
Carpenter, F. M., J. W. Folsom, E. O. Essig, A. C. Kinsey, C. T. Brues, M. 
W. Boesel, and H. E. Ewing. 
1937. Insects and arachnids from Canadian amber. Univ. Toronto 
Studies, Geol. Ser. No. 40: 7-62. 
Holland, G. P. 
1951. Insects in Canadian amber. Dept, of Ent. Newsletter Dec. 1, 1951, 
Science Service, Dept. Agric., Ottawa, Canada. 
Kirchner, G. 
1950. Amber inclusions. Endeavour 9: 70-75. 
Legg, W. M. 
1942. Collection, preparation, and statistical study of fossil insects from 
chemawinite. Senior Thesis, Dept of Biology, Princeton Univer- 
sity, 66 pp. 
Marcus, E. 
1929. Tardigrada. Bronn’s Klassen u. Ordnung d. Tierreich. Bd. V, 
Abt. IV, Buch 3 : 1-608. 
1936. Tardigrada. Das Tierreich. Leif. 6 6 : 1-340. 
Rahm, G. 
1937. Eine neue Tardigraden-Ordnung aus den heissen Quellen von 
Unzen, Insel Kyushu, Japan. Zool. Anz. 121: 65-71. 
Walker, T. D. 
1934. Chemawinite or Canadian amber. Univ. Toronto Studies, Geol. 
Ser. No. 3 6 : 5-10. 
WlCHTERMAN, R. 
1953. The biology of Paramecium, xvi + 527 pp., Blakiston, N.Y. 
