My Dear Sir

How I have longed, during my protracted illness, to reply to your enquiries, but this is the first day I have felt myself able, although still very weak & my nerves in a tremble.¹

In some way or other, I poisoned my hand, the disease spread rapidly, assumed a malignant form, & necessitated a series of acutely painful surgical operations.—

The agony endured during ten days night & day was beyond anything I ever felt, but I will not trouble you further with my own complaints, & have only said this much by way of apology for the delay in answering your kind letter.—

I should say as a general rule that birds when frightened closely adpress their feathers & it is astonishing the apparent reduction in bulk, that fear appears to produce in most species, I have noticed it most in the Melopsittacus undulatus, & in the Quail, the latter when frightened looks about half the size when undisturbed. One of the first things a bird does when recovering from a surprise is to shake out the feathers.² Some finches when angry, erect the feathers all over the body most species however only spread out the wings and tail, among the former, the Canary, Goldfinch & preeminently, the Goldfinch male, make each “dividual” feather “to stand on end like quills upon the fretful porcupine”.

I have a Goldfinch male, often in my dining room, of the most irascible disposition, even if a servant when waiting at table goes too near the cage, he at once appears a ball of erected feathers³

The irascibility of most birds, Robin⁴ excepted, is greatest during the breeding season, & many then which do not erect the feathers all over the body, erect a ruff of them round the neck, all the buntings & most of the finches do this, the Chaffinch⁵ at the same time shewing a small concealed crest at the back of the head, a spot in the same place is not concealed in the female, nor in either sex of the Brambling, “Fringilla montifringilla, nearly all when angry rush at each other with open beak & with threatening gestures.

As to birds exhibiting impatient gestures, the only birds I have observed in my aviary, which shew by signs they are hungry are the Siskins,⁶ these if hungry as soon as they see me cling to the wires of the aviary, it may be observed the species mostly seeks its food clinging like a Tit.—

There is one curious habit of captive Ratels⁷ which has much interested me, they are in the constant habit of turning summersaults, the head & back being brought with considerable force on to the ground, this appears to me to be the action, which these mellivorus mammals use, to free themselves from the bees, which must attack them in great numbers, when robbing their hives.—

I forgot to observe when speaking of the erection of feathers that the angry robin erects the feathers all over the body, the Whitethroat, C Cinerea,⁸ also erects them all around the throat.—

I shall be glad to give at all times any further information in my power.—

I take the opportunity now to mention a few other subjects—

The first bears on the Cytisus Adami.—

My Brother has but two kinds of Laburnum viz Cytisus purpureus, very erect, & Cytisus Alpinus? very pendulous, he had several stocks of the latter grafted with the purple one, & this year, the grafts being two years old, I saw in one, fairly above the stock, about four inches, a raceme of purely yellow flowers, with the usual dark markings, and above them a bunch of purely purple flowers, the branches of the graft in no way shewed an intermediate character, but had the usual rigid growth of Purpureus.—⁹ The second case bears on latent gemmules.—¹⁰

My Brother keeps a large number of Rabbits at Brenchley, not that he is a “Fancier’ of them, he has had the breed a long time & they are supposed to be pure bred English lop eared.—

Some time since, in a litter, there appeared one with the very thick coat which distinguishes the variety known as the French, the hair was remarkably long & woolly, but the peculiarity was that it was a grey a color Harrison had never seen in the French variety.—

The specimen was a male & he had from 30 to 40 young from it, without one shewing a trace of the long hair of the male parent, but curiously enough this Spring a litter appeared from a doe, not a descendant of the long hair, with 4 young of the long haired variety, and one of the usual smooth haired.—

The four young were all fawn in color.— The third case bears on the question of hereditary mutilations.—

You will recollect ⁠⟨⁠two pages missing⁠⟩⁠

the bones were put by for you, but unfortunately were mislaid & lost.—¹¹

The fourth case bears on the question of contagious variegation in plants.—

I have an ivy called the Golden lobe, by Gardeners Hedera helix aurea densa, this has twined into a common Hedera helix¹² which from its close habit I call the clinger; now the clinger has caught the yellow mottling from Aurea Densa, & thus a perfectly new variety has been formed, which was much needed as Aurea Densa was rather too arboreal in its growth.—

Had it been a mere sport I should not have attached any importance to it, but the improbability of the sport being like Aurea Densa, with which its roots & branches are so intimately intertwined, is very great unless by infection or rather perhaps contagion.

I enclose a leaf of Aurea Densa, lobed shaped, of the clinger before sporting & afterwards.—

I am surprised I have had strength to write so much, but I am so interested in your subjects & your enquiry was quite a solace during my illness.—

Believe me | Yours very sincerely | J Jenner Weir

C Darwin Esq^r.