RECORD: Darwin, C. R. 1866. Ipomoea purpurea - measurements in inches & decimals. CUL-DAR78.70-71. (John van Wyhe ed., 2002-. The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and John van Wyhe, edited by John van Wyhe 2.2023. RN2

NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR78 contains notes on experiments for Darwin's book Cross and self fertilisation.


[70]

Ipomoea purpurea - measurements in inches & decimals.

If I do 8 oz/br it will not be 1/10' of inch for

 

Crossed

Self

1' gen.

51600

39400

2d gen

50500

39800      

3d gen

46450

31700

 

48850

42100

4 gen

49525

37400

 

52500

37900

5'

75550

61425

 

90825

77325

6

113950

89700

 

46850

25200

[÷] 72

626600

481950

 

[71]

Ipomoea purpurea 1866

Crossed with other plant White Th.

Fert. with pollen of own fl. Black

Th.

Spont. self-fertilised

5 [+] 6 [+] 3 [+] 3 [+] 5 [+] 6 [+] 6 [+] 5 [+] 5 [+] 6

3. [+] 6. [+] 6 [+] 4 [+] 6 [+] (1) omit [+] 6 [+] 6 [+] 6

6. [+] 6. [+] 6. [+] 6 [+] 5 [+] 6 [+] 6 [+] 5 [+] 6 [+] 8

[=] 50 average 5.0

43 [÷] 8 [=] 5.37 average

60[÷] 10 [=] average 6.0


— not selected    taken as ripe    much pollen used—
43  43  of these seed equalled in weight  39  of  seeds marked by  Black Thread, or fert. with own pollen  

 

And 50 white thread, or I crossed seed equally 49 1/2 seed spontaneously self-fertilise

So that seeds fert with pollen of same flowers Heavier!!!

can the vars be a little sterile with each other??

too much pollen?


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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

File last updated 26 December, 2025