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Darwin Correspondence Project

From Asa Gray   4 April 1880

Herbarium of Harvard University, | Botanic Garden, Cambridge, Mass.

April 4 1880.

Dear Darwin

This just received1

I fear that the elevation of the two seeds of my Megarhiza figured was unusual.2

They were placed in a pot, the bottom filled with crocks, then common potting soil: and the seeds near an inch underground. The pot 6 or 7 inches high.

Yours ever | A. Gray


San Francisco, Cal.,

March 29, 1880.

Dear Doctor Gray,—

I received your letter of the 17th. inst Saturday afternoon (the 27th.) and went immediately out to Lone Mountain where, on a sandy hill side, I found blossoming Megarrhiza climbing over shrubby Quercus agrifolia.3 Under the vines were germinating seeds growing in almost pure sand. I put a few of the flowers and seeds into a cigar box which is now on its way across the continent.

Having just returned from botanizing near Niles, twenty five miles south of here, I happened to have in my plant case Brodiæa with forming bulbs, as well as bits of Pellæa &c. which I thought might be more interesting packing than moss.4 The two long racemes came from vines on which I could find no fertile flowers. The stem with fertile flowers must have grown from a root whose last year’s growth produced, at least, two of the accompanying seeds. The seeds which have not begun to grow were found in a drift of oak leaves. The germinating seeds were covered to a depth of from one to three inches in sand as is shown by the appearance of the stems. In a few instances the seed was one or two inches to one side of the place where the sprout appeared above ground; but generally the plumule, preceded by the radicle, seems to have been pushed directly downward four to six inches by the elongation of the united cotyledon petioles, and these were split apart by the subsequent upward growth of the plumule.5 During the Christmas vacation I observed the germination of the same species(?) of Megarrhiza in the Live Oaks of the Mokelumne River on the line of the Central Pacific R.R.6 None of the dozen or more seeds examined had sprouts more than four inches in length. All the seeds were lying on the surface of the ground (a sandy loam), and were lightly covered with leaves. In every case the sprout went directly down into the ground, and the plumule was found undeveloped near the end of the sprout which showed no signs of splitting. One seed, not so well covered as the rest, had its sprout blackened and wilted by the frost at the surface of the ground, but the underground portion seemed fresh and I doubt not the plumule would have lived. The seeds begin to grow soon after the first heavy rains; and if the plumule appeared as soon as the radicle had obtained a two or three inch hold upon the soil, as is the way with acorns, it would surely be killed by the frosts.

Some seeds which I planted a year ago in a crayon box and another shallow box invariably grew as represented in my botany; i.e., the growth was horizontal and the plumules came up four or five inches away from where the seeds were planted. Possibly the nearness of the bottom of the box—though they did not touch it—caused the sidewise growth. Possibly, too, a downward growing sprout might, when stopped by an obstacle, by its elongation push the cotyledons above ground. I cannot say certainly that the seeds I experimented with last year were of the same species as those I send you, but I think they were. Last summer, for the first I made a little effort to clear up my uncertainties regarding the several species of Megarrhiza but I was not successful. I then determined to begin early this season and study thoroughly. I shall secure seeds from many different localities from vines which shall have previously furnished blossoms and leaves. I shall send you specimens of all I collect.

I shall try to find a bit of root in condition to grow and send it to you.

With this I send a package of Lepidium which puzzles me.7

I collected it in San José a week ago. It seems to grow only on alkaline or salt flats. I found the same last year near Antioch. By-the-way I sent you in 1878 a package of Lepidium oxycarpum, Var. Strictum, Wat. of the Cal. Bot. collected in San Francisco. You did not acknowledge its receipt. I had previously sent specimens collected in San Joaquin Co. (Live Oaks) which were considered to be a possible variety of L. Menziesii. Isn’t it a well marked species?8

Yours truly | V. Rattan.

Volney Rattan, | Girls’ High School, | San Francisco, | Cal.


CD annotations

End of letter: ‘Roots of | Ipomœa | I. pandurata’9 pencil
2.7 a depth … stems. 2.8] double scored pencil
2.11 four … petioles, 2.12] double scored pencil
2.12 split … germination 2.13] scored pencil
2.15 seeds … length. 2.16] triple scored pencil
2.17 In … ground, 2.18] double scored pencil
2.20 had … ground, 2.21] double scored pencil
2.23 as the … frosts. 2.24] scored pencil
3.1 I … shallow box] triple scored pencil
3.4 Possibly … growth. 3.5] double scored pencil


CD had disagreed with Gray’s description of the germination of Megarrhiza californica (a synonym of Marah fabacea, California manroot; see letter to Asa Gray, 19 January 1880 and nn. 1 and 2). Gray evidently requested seeds and information on the germination of the plant in its native habitat from Volney Rattan, whose response is enclosed.
Gray had based the illustration and description in his Botanical text-book on Megarrhiza grown in pots (A. Gray 1879, pp. 20–1).
See n. 1, above. Lone Mountain is in west-central San Francisco. Quercus agrifolia is the California live oak, a species associated with both Marah fabacea and M. oregana (western wild cucumber or coastal manroot; see Stocking 1955, p. 118). Gray had been unsure about the identity of seeds sent to CD (see letter from Asa Gray, 11 March 1880).
Brodiaea is the genus of cluster-lilies; Pellaea is the genus of cliff-brake, a type of fern.
Rattan’s description of germination agrees with that of CD (see letter to Asa Gray, 19 January 1880).
The Mokelumne river is in northern California. The trees referred to are canyon live oaks (Quercus chrysolepis). RR.: railroad.
Lepidium is the genus of pepperweed.
Lepidium oxycarpum is forked pepperweed; L. menziesii is a synonym of L. virginicum ssp. menziesii, Menzies’ pepperweed.
CD’s annotation is a note for his reply to Gray (see letter to Asa Gray, 19 April 1880). Ipomoea pandurata is man-of-the-earth or wild potato vine (see letter from Asa Gray, [1 April 1880] and n. 2).


Gray, Asa. 1879. Gray’s botanical text-book. Vol. I. Structural botany or organography on the basis of morphology. To which is added the principles of taxonomy and phytography, and a glossary of botanical terms. 6th edition. New York and Chicago: Ivison, Blakeman, and Company.

Stocking, Kenneth M. 1955. Some taxonomic and ecological considerations of the genus Marah (Cucurbitaceae). Madroño 13: 113–37.


Encloses a letter from Volney Rattan of California.

Letter details

Letter no.
Asa Gray
Charles Robert Darwin
Sent from
Herbarium of Harvard
Source of text
DAR 209.6: 204–6
Physical description
ALS 1p †

Please cite as

Darwin Correspondence Project, “Letter no. 12562,” accessed on 15 April 2024,