RECORD: Darwin, C. R. 1878.06.15-21. Ipomoea nil /Draft of Cross and self fertilisation. CUL-DAR209.4.187-189. (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 9.2022. 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-DAR209.4 contains materials for Darwin's book Movement in plants (1880).

Draft of Cross and self fertilisation in the hand of Ebenezer Norman with corrections by Darwin.


[187]

Jun 15th Ipomoea nil tip 6 inches from glass

8° am

9 23 up considerably, little to left

10 30' up little to right

12° a little up & to left

1°   down & to left

2° .5 down & to right

3° down— tied up hypoctyl & so had to make new dot higher

4' down & to right

5° down, nearly straight

6° down

7° down little

9. down do

10 30 a very little down

10. 43 Bell-glass

11. 30' down  

1. 30 do

3. 30 lower

}

6. 30 still down 6° 45' do

6. 50   vertical glass

8° 25 up little

change between these Hours

9° 10   almost same spot

10. 15 .   do.   do

12° a little down — cold or darkness paralysed

12. 55 a little down

2° an atom down

3° an atom up

4. 30 do

6 same spot — paralysed

8' 30 atom down

10. 35 a do

17. 6° 45 went down moderately during night

(Abstracted)

[187v]

few flowers are born conspicuous and odoriferous. Of all colours white is the prevailing one; and of white flowers a considerably larger proportion namely 14.6 per cent smell sweetly than of any other colour; of the next most favourable colour, red, only 8.2 per cent are odoriferous.* The larger proportion sweet-smelling flowers amongst those of white flowers colour may depend in part on flowers which are fertilised by moths requiring the double aid of conspicuousness in the dusk and of odour. So close is the adaptation, or so great is the economy of nature, that flowers which are

[Cross and self fertilisation, p. 374: "Not a few flowers are both conspicuous and odoriferous. Of all colours, white is the prevailing one; and of white flowers a considerably larger proportion smell sweetly than of any other colour, namely, 14.6 per cent; of red, only 8.2 per cent are odoriferous.† The fact of a larger proportion of white flowers smelling sweetly may depend in part on those which are fertilised by moths requiring the double aid of conspicuousness in the dusk and of odour. So great is the economy of nature, that most flowers which are fertilised by crepuscular or nocturnal insects emit their odour chiefly or exclusively in the evening."]

[188]

Cotton Ipomoea nil Jun 20th

4° 22'

4. 53 down  Temp 19 3/4 C.

5. 35 do

7. 15 do    (Skylight)

8° 53 do.

10. 9 do

Glass

 

10. 18   Cotton   (Bell glass Bedroom)

12° 30 an atom down

3° 45 risen considerably    Distance combined — Ipom

6 12 fallen a little

21st

6° 20' Case Ipomaea

6° 42 risen moderately

7' 32    do.

8. 5   fallen

8 50   risen

9. 28   down

10. 10   skylight   do

10 47   a little up

11. 37   down

12. 35   a good way up

12 58   down

1. 30 up

2. 15 a little up & to left

2. 27 far up

3. 2 a little high

3. 29 down

[188v]

50 661

Chap. E 10

On the relation between the structure and conspicuousness of flowers, the visits of insects, and the advantages from cross-fertilisation.

It has already been shown that there is no close

[Cross and self fertilisation, p. 381: "On the Relation between the Structure and Conspicuousness of Flowers, the Visits of Insects, and the Advantages of Cross-fertilisation.
It has already been shown that there is no close relation between the number of seeds produced by flowers when crossed and self-fertilised, and the degree to which their offspring are aaffected by the two processes."]

[189]

Ipomoea continued (21st)

4° down & to left

4° 30 far up & to left

5 up & to right

5. 30 down & to right

6°   far down

(no more 1/2 hrs observations)

7° 15 high up

9° far down

10. 30 to left & down

22d

6°. 45' ⨀

8

[189v]

*page 54

In answer to a question by me, the editor of an entomological journal writes,─ "The Depressariæ, as is notorious to every collection of Noctuæ, come very freely to sugar, and

[Cross and self fertilisation, p. 383, n†: "† In answer to a question by me, the editor of an entomological journal writes—"The Depressariae, as is notorious to every collector of Noctuae, come very freely to sugar, and no doubt naturally visit flowers:" the 'Entomologists' Weekly Intelligencer' 1860 page 103."]


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

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