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Darwin Correspondence Project

From James Murie   1 May 1868

Zoological Society’s Gardens, | Regent’s Park, | London, N.W.

1st. May 1868

Dear Sir

It is only lately that I have had the opportunity of examining the specimen, regarding which you formerly asked me some questions about,—the Bornean Ape macacus inornatus Gray.1

Previously I acquainted you with the external appearances and measurements of which you took notes at the time;2 but in case these are mislaid I here add.

—In the living animal (a young female) there are two callosities, each 112 inch long. The buttocks around around these callosities are flesh coloured or rosy in hue and covered with slight downy hairs.

Tail 1 inch in length, circumference at its root 112 inches,—there is a slight tendency to curvature upwards.

Of the skeleton, the rough sketch of the pelvic parts may serve to convey a better notion of the relation of parts than a long description.

Caudal vert 9 to 10 in number   The three first have transverse processes. Together the 3 vertebrae have a length of 0.8 inch long. The remainder of the caudal vertebrae are devoid of transverse processes and the two last are mere ossicles partly coalesced.

These 6 or 7 terminal caudals are together 1 inch long.

The tail vertebrae therefore altogether measure 1.8 inch long—and the terminal point reaches backwards no further than the ischial prominences,—indeed if a vertical line is dropped from the point of the tail it falls upon or is slightly in advance of the superior (Posterior in human anatomy)3 angle of the ischeum while the inferior (or anterior of human anatomy lies behind that vertical line.4

I suppose the (free?) tail when living must have enclosed only those caudal vertebrae without transverse processes.5

I am | Dear Sir | Yours with much esteem | James Murie

C. Darwin Esqr



CD annotations

4.1 Tail … upwards. 4.2] scored pencil


A Macacus inornatus acquired by the Zoological Society of London in 1866 was described by John Edward Gray in the Proceedings of the Zoological Society of London (1866): 202–3, where there is also an illustration of it. The macaque died in the same year it was acquired (Murie 1872, p. 721). Murie later established that Macacus inornatus was a synonym of M. maurus (now Macaca maura); see ibid., pp. 721–2. No previous correspondence between CD and Murie has been found, but CD visited the Zoological Society’s Gardens frequently during his visit to London in March (letter to J. J. Weir, 4 April [1868]).
CD’s notes have not been found in the Darwin Archive–CUL; however, there is an undated note, not in CD’s hand, in DAR 80: A16, which says, ‘In Gray’s cat of Br Mus (bone & skeleton the caudal vertebrae in Macacus differ from 24 to 3, the Barbary ape having only 3. In M. inornatus the tail is only 1 inch long and 112 in circumce. Dr Murie will write about vertebrae’.
‘Posterior in human anatomy’ is circled and interlined in the original text.
See Murie 1872, pp. 724–6 and fig. 1. Ischeum: i.e. ischium.
CD cites Murie for the information in this letter in Descent 1: 151, suggesting that the three embedded caudal vertebrae of Macacus inornatus corresponded to the four coalesced vertebrae of the human os coccyx.


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

Murie, James. 1872. Observations on the macaques.– I. The Bornean ape. [Read 4 June 1872.] Proceedings of the Zoological Society of London (1872): 721–8.


Measurements of the Bornean ape (Macacus inornatus, Gray). [See Descent 1: 151.]

Letter details

Letter no.
James Murie
Charles Robert Darwin
Sent from
Zoological Society Gardens
Source of text
DAR 80: B124, B156–7
Physical description
4pp † encl 1p (sketch)

Please cite as

Darwin Correspondence Project, “Letter no. 6155,” accessed on 22 October 2019,

Also published in The Correspondence of Charles Darwin, vol. 16