Notebook recording Bateson and Punnett's experiments with sweet pea crosses in 1904.

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 often recorded, together with other observations on the plants such as colour.

Some records are unusually detailed [e.g. pp 70v-75 and 80v-81r]. Plants marked 'important' or 'v. important' include those on [pp 49v-50r, 115v-118r, 122v-123v, 128v-130v and 147v-148r]. There are notes on crosses on [pp. 238v-239v].