From Edward Westey Janson   25 May 1868

30, Museum Street, | London, | W.C.

25th May 1868

Charles Darwin, Esq., M.A., F.R.S., etc | Down, | Bromley, Kent | S.E

Dear Sir,

Mr Bates, having on Saturday afternoon selected a few Lamellicorn Beetles, destined, I believe, to assist you in the investigation in which you are engaged, has requested me to pack and send them on to you to the care of the Down Postman, Bromley, Kent; and I beg to advise that, having carefully packed them, I have this evening forwarded them, p. Rail, so addressed.1

Amongst the Lamellicornia, the family Dynastidae offers the most numerous instance of the presence of stridulating organs, and of diversity of structure in the apparatus. Trox sabulosus emits a sound equal in intensity to the squeak of a mouse, and amongst other groups of Coleoptera, Necrophorus, Lixus, and Acalles may be cited, and Mr Frederick Smith this morning mentioned to me that the female of a species of the hymenopterous genus Mutilla possesses the faculty in a high degree2

Trusting that the insects will reach you safely and prove of service, and tendering you my best services in case of need | I am, | Dear Sir, | Yours very truly & respectfully, | Edward W. Janson

[Enclosure]

30 Museum Street
London, 25th May 1868
Charles Darwin, Esq
To E. W. Janson
Natural History & General Agent, and Bookseller
2 Phanaeus carnifex. F.3 ⚥ @ 1/ £—. 2. —
2 Copris (Pinotus) carolina, L4 ⚥ @ 1/ .—. 2. —
3 Geotrupes stercorarius L.5 1 ♂. 2 ♀ @ 3d .—. —. 9
2 Bolboceras farctus. F.6 ⚥ @ 6d .—. 1. —
2 Lethrus cephalotes, F.7 ⚥ @ 1/6 .—. 3. —
2 Oryctes nasicornis, L.8 ⚥ @ 1/ .—. 2. —
2 Geotrupes typhoeus. L.9 ⚥ @ 3d .—. —. 6.
2 Bubas Bison. F.10 ⚥ @ 4d .—. —. 8.
2 Onitis furcifer, Rossi11 ⚥ @ 4d .—. —. 8.
Box, case, packing & booking —. 1. 5.
£ —. 14. —.

CD annotations

2.5 Mr … degree 2.6] double scored pencil
Top of letter: ‘Mutilla—stridulating’ pencil
Top of enclosure: ‘(Please return these)’ pencil

End of table:

‘ add 2 6
16 6 ’
ink

1
Janson refers to Henry Walter Bates. See letter from H. W. Bates, 20 May 1868, and letter to H. W. Bates, 21 May [1868]. The previous Saturday was 23 May. CD mentioned that he was indebted to Janson for information and specimens in Descent 1: 379 n. 70.
2
CD was interested in stridulating insects (see letter to H. W. Bates, 21 May [1868]). The subfamily Dynastinae of the family Scarabaeidae are rhinoceros beetles; CD discussed the stridulation of the New World tribe of Dynastinae, the Dynastini, in Descent 1: 347. CD mentioned the stridulation of Trox sabulosus in Descent 1: 380. Nicrophorus is a genus in the carrion beetle family, Silphidae: CD discussed the stridulation of Necrophorus (Nicrophorus) in Descent 1: 378. Lixus and Acalles are genera in the family Curculionidae; CD discussed the stridulation of Acalles in Descent 1: 384. Mutilla is a parasitic wasp of the family Mutillidae, often known as the velvet ant: CD discussed the stridulation of M. europaea in Descent 1: 366.
3
CD discussed the variation of the horns of the male Phanaeus carnifex in Descent 1: 370, but did not cite his own observations. The species namer is recorded as Carl von Linné (Linnaeus), not Johann Christian Fabricius.
4
Copris or Pinotus carolinus is now Dichotomius carolinus, the Carolina copris.
5
CD described his observations on Geotrupes stercorarius in Descent 1: 380 and 382.
6
Bolboceras farctus is probably now Bolbocerosoma farctum.
7
Lethrus is in the family Geotrupidae.
8
CD described sexual differences in the stridulating organs of Oryctes nasicornis in Descent 1: 383; Oryctes is in the family Scarabaeidae, subfamily Dynastinae.
9
Geotrupes typhoeus is now Typhaeus typhoeus (the minotaur beetle), in the family Geotrupidae. CD described his observations on the stridulating organs of Typhaeus in Descent 1: 378 and 380.
10
CD discussed the thoracic projection of Bubas bison in Descent 1: 372–3; Bubas is in the family Scarabaeidae, subfamily Scarabaeinae.
11
Now Chironitis furcifer. CD discussed the projections on the femur, head, and thorax of Onitis furcifer in Descent 1: 371–3.

Please cite as “DCP-LETT-6209,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-6209