TY  - BOOK
AU  - Ritchie, John W.
AU  - Day, Chapin Walker.
AU  - Ritchie, Margaret.
TI  - Biology and human affairs
AV  - QH308.5 .R5
U1  - 574 
PY  - 1941///
CY  - Yonkers-on-Hudson, N.Y.
PB  - World book
KW  - Biology
N1  - At head of title: By John W. Ritchie; Includes bibliographical references and index
ER  -