Notebook recording Bateson and Punnett's experiments with sweet pea crosses in 1909.

Original pagination runs 1-4 [now pp ii-v; excised entries for 1907], followed by a page listing crosses to be made for 1909, then records paginated 1-100 of which 97-99 are blank. There are maps of the plots where plants were set out on [pp 99v-101].

The general format of the record is that the parents are recorded as numbers with a superscript or sometimes as a named variety. Since sweet peas can be selfed, some crosses have only a single parent. The date of sowing and the date of planting out are recorded, together with other observations on the plants such as colour, height and petal form.

The plants recorded on [pp 60v-61] are marked 'some of the largest plants we have had'. Some entries include tables of progeny [e.g. pp 93v-96].