Slide showing table 23: 'Frequency distribution for Corolla length in a cross-between varieties of Nicotiana longiflora'. Slide shows table 23: 'Frequency distribution for Corolla length in a cross-between varieties of Nicotiana longiflora (After East)'. Row headings: 'designation number', 'year', 'generation', 'parent size', 'class centers in millimeters'. Column headings: 'designation number': '383', '383', '383', '330', '330', '330', '383 x 330', '(383 x 330)1', '(383 x 330)2', '(383 x 330)1-1', (383 x 330)1-2', '(383 x 330)1-3', '(383 x 330)1-4', '(383 x 330)2-1)', '(383 x 330)2-3', '(383 x 330)2-4', '(383 x 330)2-5', '(383 x 330)2-6', '(383 x 330)1-2-1', '(383 x 330)1-3-1', '(383 x 330)2-6-1', '(383 x 330)2-6-2', '(383 x 330)1-3-1-1', '(383 x 330)2-6-2-1'. The years date between 1911 and 1915. Late 19th to early 20th century