skip to content

Darwin Correspondence Project

From J. D. Hooker   30 August 1873

Royal Gardens Kew

Aug 30. 1873

My dear Darwin

The three plants sent in the box to be named1 are

i The Common scarlet runner Phaseolus Multiflorus, W. = P. coccineus, Lam.2

ii. wild Marjoram, Origanum vulgare3

iii Petunia violacea, Ldl. garden form, perhaps a hybrid.4

The dwarf Kidney Bean or Haricot is Phaseolus vulgaris it has ovate striate bracts at the base of the calyx & few flowers—5

P. multiflorus has many flowers and rough pods.

The Lobelia ramosa var. Snow-flake was mentioned in the Gardener’s Chronicle for 1866. It is probably a white variety of a W. Australian species L. tenuior R. Br.6 A larger form of it was figured in C Bot. Mag. t. 3784 as L. heterophylla7

The sweet smelling Marvel of Peru is Mirabilis longiflora, L.

With regard to the absorption of water by leaves Duchartre believes that the aerial parts of plants do not absorb dew deposited upon them (Ann. des sc. nat. 4e sér. xv. 156)8

McNab found that detached leaves (end of petiole closed with sealing wax) absorbed from 1.55 to 7.35% of their weight when immersed in water   Detached leaves kept in a saturated atmosphere for 18 hours did not appreciably vary in weight either in sun or shade (Trans. Bot. Soc. Edin. xi. p. 54)9   Cailletet points out that the foliage of plants will absorb water if the supply to the roots is insufficient. He particularly points to Bromeliaceæ such as Pourretia which will live for years without possessing any roots if they are occasionally syringed (Ann. des sc. Nat. Ve. sér. xiv. pp. 243–245)10

E. Faivre finds that the water contained in ascidia is partially reabsorbed by the plant. The experiments were made by introducing into a pitcher a measured quantity of water & then inclosing the pitcher in a dry glass vessel. After the end of some days the water contained in the pitcher together with that exhaled & condensed in the glass vessel was less than the quantity originally introduced—(Revue Scient. Septr. 1872 p. 279)11

Linnæus on Sleeping Plants is to be found in Amœnitates academicæ iv 333–350 Somnus plantarum in dissertatione academica propositus præside Dom. doct. Carolo Linnæo a Petro Bremes12

The dichogamy of Eucalyptus is not an easy matter to decide. Mr Dyer has looked at E. corynocalyx and thinks it is slightly protandrous but the nature of the stigma makes it difficult to ascertain by inspection the exact point at which it is fit for the reception of pollen.13 It seems on the whole, however, to be in arrear of the stamens

We have been trying Mimosa commonly called sensitiva*14 with water flicked from a brush. It seems to have no effect whatever but the plant is tolerant of more considerable impulses than the blow of a drop of water could give it

The Mimosa at Down is M. pudica

Ever Yours | J D Hooker

*The true sensitiva is Brazilian   The plant usually cultivated as this is N Peruvian M. albida, & is that we have. & experimented upon.15

M. sensitiva has the leaves only lentē sensibilia16

CD annotations

1.1 The three … Br. 4.2] crossed ink
1.3 ii.... vulgare] tick added pencil; ‘This is correct though apparently long cultivated’ pencil
4.3 A … heterophylla] crossed pencil; ‘Bot. Mag. p 3784 on L. heterophylla’ added ink; crossed pencil
5.1 The … L.] double scored red crayon; ‘Hairsadded pencil
8.1 E.... p. 279) 8.6] crossed pencil
9.1 Amœnitates academicæ] marked with cross pencil
10.1 The dichogamy … stamens 10.4] crossed pencil
12.1 at Down] underl red crayon
12.1 M. pudica] underl red crayon
Top of letter: ‘Hooker | Experiments on Crossing’ pencil


See letter from J. D. Hooker, 3 August 1873. Hooker may have told CD to send the plants for identification during his visit to CD on 23 August 1873 (Emma Darwin’s diary (DAR 242)).
In Cross and self fertilisation, p. 150, CD referred to Phaseolus multiflorus as the scarlet-runner of English gardeners and P. coccineus of Lamarck. It is now known by the latter name.
Origanum vulgare is also known as oregano.
Petunia violacea is a synonym of P. integrifolia, the violet-flowered petunia. The garden petunia is now P. hybrida.
Phaseolus vulgaris is the common bean; it has several cultivated varieties including kidney beans and haricot or pea beans.
Lobelia tenuior is a blue lobelia. CD added a note on L. ramosa var. ‘Snow-flake’ to Cross and self fertilisation, p. 176, and cited William Turner Thiselton-Dyer for the information. The letter is written mostly in Thiselton-Dyer’s hand and he evidently provided some of the information for Hooker. Thiselton-Dyer had been employed part-time at Kew from the end of 1872, editing Hooker’s Flora of British India (J. D. Hooker 1875–97) and also describing Indian species of six families of flowering plants (DNB).
Hooker refers to Curtis’s Botanical Magazine n.s. 13 (1840): table 3784. The common name given is the various-leaved lobelia. Lobelia heterophylla and L. tenuior are now considered to be separate species.
Pierre Etienne Simon Duchartre, in a paper detailing his experimental research on the effects of dew and fog on plants, had concluded, contrary to general belief, that dew on the aerial parts of plants acted like a sort of localised rain that was eventually absorbed in the ground (Duchartre 1861, p. 156).
William Ramsay McNab, in his article ‘Experiments on the transpiration of watery fluid by leaves’ (M’Nab 1870, p. 54), concluded that leaves did not absorb water from the atmosphere but did absorb varying amounts when immersed in water.
Louis Paul Cailletet studied the absorption of water by leaves of Pourretia (a former bromeliad genus now subsumed within Puya), concluding that some uptake of water was possible (Cailletet 1871, p. 245).
Ernest Faivre’s experiments on the ascidia or pitchers of Nepenthes distillatoria were reported in the Revue scientifique de la France et de l’étranger, 21 September 1872, pp. 279–80. The pitchers of Nepenthes are modified leaf blades.
Hooker refers to Carl von Linné (Carolus Linnaeus) and Peter Petersson Bremer, and to Linnaeus 1755 (The sleep of plants, proposed as an academic dissertation under the supervision of Dr Carolus Linnaeus by Peter Bremer), later republished in the second edition of Amoenitates academicae (Linnaeus 1759–64, 4: 333–50).
Eucalyptus corynocalyx (now E. cladocalyx, the sugar gum) exhibits a form of dichogamy in which the anthers dehisce or open before the stigma becomes receptive (protandry). In most eucalyptus flowers, stigmas become sticky when receptive.
Mimosa sensitiva is native to Brazil and Peru.
Mimosa albida is widely distributed from Mexico to northern and western South America, including Peru and north-western Brazil (Rondônia).
Lente sensibilia: slowly responsive (Latin).


Identifies three plants sent by CD.

Letter details

Letter no.
Joseph Dalton Hooker
Charles Robert Darwin
Sent from
Source of text
DAR 77: 173; DAR 209.6: 205
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 9034,” accessed on 26 April 2019,

Also published in The Correspondence of Charles Darwin, vol. 21