From W. E. Darwin   [7–15 April 1868]1

Langstaff says that he never has seen the platysma act & always looks out.2

His belief from his own experience is that it is what may be called rudimentary in Human Beings.

There is often very bad dyspnoea under Chloroform and he has lately seen a bad case of Tetynus3 where the head was thrown far back & the muscles from the shoulders acting violently, the mouth was violently clenched, & from the position of head he should have thought the platysma ought to have acted, as the clenching of the jaws would give it a purchase to act from.4

I will ask him again about this case

incomplete

1
The date range is established by the relationship between this letter and the letters from W. E. Darwin, [7 April 1868] and [15 April 1868].
2
In Expression, p. 301, CD cited Charles Langstaff’s observation that the platysma did not contract in patients with extreme respiratory difficulties. The platysma, or platysma myoides, was described by CD as a rudimentary muscle in humans (Descent 1: 19). See also letter from St G. J. Mivart, 6 April 1868, n. 2.
3
Tetanus, or lockjaw.
4
Having received information from various sources, CD concluded that the platysma did contract in patients suffering from lockjaw (Expression, p. 301).

Please cite as “DCP-LETT-6076,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-6076