RECORD: Darwin, C. R. [ny][.05]22-[.05]25. Crinum capense / Draft of Cross and self fertilisation. CUL-DAR209.3.123. (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 11.2022. 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-DAR209.3 contains materials for Darwin's book Movement in plants (1880).

Draft is in the hand of Ebenezer Norman with corrections by Darwin. The text of the draft corresponds to Cross and self fertilisation, pp. 345; 347, respectively.


[123]

Crinum Capense Vertical glass

obscure light

Right Hand.      Left Hand

[sketch]

straw

11°. 30'            11°. 30' from the right on edge of glass

12° noon straight far to right on edge of glass

uppermost black dot   12° risen far above glass no mark

12° changed mark ⨀   ⸻

12. 34° far to right      12. 34 has travelled to left but on glass

2° 47' spot on Bell glass         2° 47'

3. 4 to left & up          3. 4' a little down

3. 56 up & to left        3 56 up & to left

4. 30 almost same course more horizontal             4. 30 same course

5 20 to left & up         5 15 . up almost vertically

6— up             6° down

7. 20 to left & up        7° 20 to left & little up

9. 5 far to left 9. 5 up & to left

10. 35' far to left         10. 35 risen & to left

23d

6° 45. a.m        6° 45' am

8 gone back to right    8 to right & little down

9° to right & up — short way             9° up & to left short way up

10. 20' to right & down          10. 20' to left & little up

12 to left         12 same course very short distance

2° 5 a good way to left           2°. 5 same course

3. 5 to left & down     3. 5 do

4. 5 same course         4. 5 up & left

6— do             6 to left

7°. 30' a little up do 7. 30 to left & much up

9°. gone on lower side & parallel.      9° to right & back

11° 5 right & horizontal         11 5' to right & little up

 

 

24th

 

6°. 45   6° 45'

8 down & to right       8° same spot

9. 30 risen & gone back to left           9° 30' risend & to left

10. 30 back to right, little rise            10. 30' to left & down

11. 30 vertically up     11° 30 to left

1° down & to right almost same spot           1° same course

2° down on former line           2 do

3 to right         3° same course only an atom

4° down & across first line     4° same course

5. 10' little to right      5. 10 .do

7. up—            7° down

8° 45 — good way to left       8° 45 risen a little

10. 45 vertically up     10 45 same course

25

6° 40'         6° 40'

8° hardly moved    8° same course as night

9. 15 gone back     9. 15 d

10. 15        10. 15

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Chapter 9

self-fertilised plant long cultivated under the same conditions.

We may further infer that the converse of this occurs when with plants which are self-fertile in their native country, but become self-fertile under different changed conditions)

(We know that self-fertilised seedlings are inferior in many respects to those from a cross with a distant individual; and as with plants in a state of nature [illeg] [na]turally pollen from the same flowers can hardly fail to be often placed by insects or by the wind [in] their stigmas, of the same flowers, It it seems at first sight highly probable [th]at self-fertility has been gradually acquired through natural selection in

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individuals are absolutely alike. Therefore we can hardly avoid believing the conclusion that differences of an analogous nature in the reproductive system are sufficient to excite the mutual action of the sexual elements, and that unless there be such differentiation fertility fails.)

The appearance of highly self-fertilised varieties. We have just seen that self-fertility is an extremely variable character in certain cases, & we have differ much in degree, both with the species of the same genus, & sometimes with the individuals of the same species. We shall now to consider facts, observed on two probably on this three occasions, of the appearance of on two or three occasions of the varieties, which when self-fertilised were more fertile than their parents, or than the intercrossed plants of the corresponding generation.


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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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