skip to content

Darwin Correspondence Project

From Harrison William Weir   23 March 1869

Weirleigh | Brenchley Kent.

March 23rd. 1869

Dear Sir

Since I last wrote to you I have been collecting information as to the numbers of the different sexes in the families of birds and Animals1

As regards Pigs

Most of the breeders that I have consulted on the matter tell me that the average of males to females is about 7 to 6,2 but my own observation though limited makes them nearly if not quite 8 males to 6 females and one litter that I met with of 13 (of which I purchased 2) there were no less than 12 males and only 1 female. Once at Halifax I was shewn one of neither sex a little of each.

As regards Pigeons

There are more cocks then hens, I have often bred two cocks in a nest, but seldom two hens.3 The hen in the nest is generally the weaker bird of the two, and is much more liable to die in rearing. Supposing that you were breeding from two blues, the hen of the two young ones frequently (perhaps not very so) comes out a silver color, but I do not remember a visa versa case. In breeding from two reds the hen in nest is sometimes yellow while the cock bird is red.

With regards to the likes and dislikes

Some of the fanciers have informed me that their hens will often take a fancy to one particular cock and often leave their own mates   this I have also known to be the case with my own birds but not frequent


Mr. Baker4 of Leadenhall market tells me that in breeding the above, he generally gets 4 to 5 Cocks to 1 hen. When out shooting (where we have killed all rising or rather shot at) I have noticed the great preponderance of cocks, when the bag has been laid out.


Mr. Ridpeth of Manchester keeping blue Rock pigeons has noticed that they drive off any other color, such as yellow, reds, and whites5

Tame Rabbits.

I have kept rabbits many years, and have noticed the far greater number of bucks than does. I kept an account last year 1868 on purpose for you and out of three litters 15 in all I only had one doe. I will keep an acct again this year.6

I have had my Rabbits some generations back, but curiously enough I bred a long hair last year   It is grey and a buck. The hair is very long. I have kept it on purpose to see if the breed from it will be long haired. I have one litter now about 6 weeks old from it all smooth   I shall try again as an experiment or if you would like to have it I shall be most happy to send it you. I found that the doe rabbits did not care so much for his attentions as the smooth buck   Rabbits are different from any other any animals I know. They will receive the attention of the buck though with young, even up to the day before kindling and if put to different bucks seem not particular as to how many   this is curious so excuse my mentioning it as I know of no other animal like it.

Breeding singing birds

I am informed that the best singing bird (cock) generally gets a mate first when they are bred in rooms.

A Poultry breeder told me a few days since (He keeps Bramah Poutras and Spanish) that some years his Spanish run mostly to cocks and the Bramahs the opposite.7 Then the next year the Bramah are mostly cocks possibly, but he seems to have the idea that there is something in the season that helps the breeding in some way, this (if true) seems to carry out my notice of the sheep some seasons having more twins

CD annotations

1.1 Since … birds 1.2] crossed blue crayon
2.1 As … each. 3.5] crossed pencil
5.3 that … bird 5.6] crossed blue crayon
6.1 With … the case 7.3] crossed blue crayon
10.1 Pigeons … that 11.1] crossed blue crayon
11.1 they … whites 11.2] crossed blue crayon
12.1 Tame Rabbits.... this year. 13.3] crossed pencil
13.2 out of … one doe. 13.3] tick added blue crayon
14.1 I have one … all smooth 14.4] tick added blue crayon
14.1 I have … like it. 14.9] crossed blue crayon
14.4 I shall … send it you. 14.5] scored blue crayon; tick added blue crayon
15.1 Breeding … rooms. 16.2] ‘Harrison Weir’ added pencil
17.1 A Poultry … more twins 17.5] crossed blue crayon
Top of letter: ‘Harrison Weir’ ink
End of letter: ‘than at others.’ ink


The last extant letter from Weir was that of 28 March 1868 (Correspondence vol. 16).
In Descent 1: 305, CD cited Weir for this information.
In Descent 1: 306, CD cited Weir for this information.
Charles Newcomb Baker.
In Descent 2: 118, CD cited Weir for this information. Weir refers to Thomas Hardwick Ridpeth.
In Descent 1: 305, CD cited Weir for this information.
Weir refers to Brahmaputra (often shortened to ‘Brahma’) and Spanish varieties of domestic fowl.


Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 27 vols to date. Cambridge: Cambridge University Press. 1985–.

Descent: The descent of man, and selection in relation to sex. By Charles Darwin. 2 vols. London: John Murray. 1871.


Proportion of sexes in pigeons, pigs, and pheasants.

Sexual preferences of females.

Letter details

Letter no.
Harrison William Weir
Charles Robert Darwin
Sent from
Source of text
DAR 86: C10, DAR 84.1: 118
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 6680,” accessed on 24 September 2021,

Also published in The Correspondence of Charles Darwin, vol. 17