|1.||Thaddeus (ˈθædɪəs). 1792--1868, US Radical Republican politician. An opponent of slavery, he supported Reconstruction and entered the resolution calling for the impeachment of President Andrew Johnson|
|2.||Wallace. 1879--1955, US poet, whose books include the collections Harmonium (1923), The Man with the Blue Guitar (1937), and Transport to Summer (1947)|
|Stevens (stē'vənz) Pronunciation Key
American biologist who identified the role of X and Y chromosomes in determining the sex of an organism. Stevens studied the chromosomes of mealworm beetles, first establishing that chromosomes are inherited in pairs. She later showed that eggs fertilized by X-carrying sperm produced female offspring, while Y-carrying sperm produced male offspring. She extended this work to studies of sex determination in various plants and insects.