From James Torbitt   [18 March 1880]1

[Enclosure]

many varieties of the potato which are so prolific and so free from the disease, that they leave, after separating the few diseased tubers, a larger crop of sound tubers than the common old varieties give of sound and diseased tubers taken together.

Knight found (1)34 tons potatoes per statute acre.2 I have found as much as (2)24 tons tubers, and (3)13 tons berries, while the average for Ireland last season according to statistics just published was 26(4) cwt. And no berries at all— now what would be thought of a crop of strawberries which was all roots and foliage and no berries?(5) And yet the capacity of sexual reproduction, is as well developed in the potato during the second and third years of life, as it is in the strawberry. Why does it fail in the 17th. year of life as with the Champion?3

1)

2) at the rate of

3)

4 hundred weight

5 fruit of the plant

AL incomplete

CD annotations

1.1 many … together. 1.3] scored red crayon
2.1 Knight ] double underl pencil; ‘Knight’ added pencil
2.2 berries ] underl pencil
2.3 was ] double underl pencil
2.3 cwt ] underl pencil; ‘cwt’ added pencil
2.3 no berries ] double underl pencil; ‘?’ in margin pencil; ‘tons ?? | cwt’ interl pencil after ‘no’
Top of letter: ‘has been recopied’4 pencil
1
The date is established by the relationship between this letter and the letters to James Torbitt, 17 March [1880] and 20 March 1880; see also n. 4, below.
2
Torbitt had previously referred to the potato experiments of Thomas Andrew Knight in the enclosure to his letter of 24 February 1878 (Correspondence vol. 26).
4
CD had asked Torbitt to return a page of manuscript about ‘berries’ (see letter to James Torbitt, 17 March [1880]). Torbitt added the last two sentences and the footnotes before enclosing the page in a letter of 18 March 1880 that is now missing (see letter to James Torbitt, 20 March 1880). The page is numbered ‘9’ and is part of a larger manuscript, the rest of which has not been found.

Please cite as “DCP-LETT-12381,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-12381