A typical letter handwritten by author in English and signed by author.
An original MS
Total Pages : 4
Pages with text: 4
Transcriber: Coleman, David
Transcription date: May 11, 2015
Scrutiny: 11/05/2015 - Benny, Ruth;
Signed off: no
Zoological Society's Gardens,
April 16 1886
My dear Sir
The only instance of a well marked series of structural variations in a given species known to me at first hand is in a species of earthworm -- Perionyx excavatus (Perrier). Out of 2,000 examples I found 13 specimens showing eleven well marked variations.
The characters of the species are briefly as follows
Colour (in alcohol) reddish violet above dirty yellow beneath
Setae forming a complete row round each segment
Two pairs spermathecae -- spherical pouches without diverticula -- in segments 8 & 9. [] Two pairs of testes in 11 & 12.
Ovary a single pair in 13.
Oviduct open by a common pore in the middle of segment 14
Vasa deferentia open separately on to 18 each furnished at its termination with a large 'prostate' gland.
The variations observed were (1) in the number of spermathecae (3 or 4 pairs instead of two) & in their position
(2) in the ovaries & oviducts; there were occasionally two pairs of ovaries each with its own oviduct; the external apertures of these varied in position [1 word illeg.] upon 13 & 14, 14 & 15 or 15 & 16. Occasionally when there was only the normal single oviducal pore present it varied in position (once on 10th & once on 11th segment)
(3) in the male generaratic pores vary in position from 14 -- 20 -- I found them in different examples on all of these segments. In one instance there were two pairs instead of the normal single [] 2 pair -- in this case each of the four apertures had its own prostrate gland.
The above is a brief sketch of the variations I have noted; I would impress upon you the fact that all or nearly all of the above variations are found normally in other genera & species. For instance the genus Acanthodrilus has four male generatic pores. The genera Euclipidrilus[?] & Chretogartus[?] have been described as forming two or three pairs of ovaries.
I would also venture to suggest to you that the group of earthworm is one particularly favourable to showing variations such as are necessary to prove your & Darwin's views. They evidently have some relation ---- as regards rapid multiplication ---- with the progress of agriculture; & the enormous increase in individuals must lead to the occurrence of numerous variations which may be the first time in the [] development of new species.
At any rate I am able to give you the above mentioned varieties of a particular species; & I may remind you that the group consists of numerous distinct species & genera with a very similar outer[?] and form but exibiting well marked structural differences.
Hoping these facts may be of some service to you[.]
I remain | Very faithfully yours | Frank E. Beddard3 [signature] 4
A. R. Wallace Esqe
1. Manuscript text in top right hand corner reads "171".
2. Manuscript text in top right hand corner reads "172".
3. Beddard, Frank Evers FRS FRSE (1858 – 1925). English zoologist. Beddard was naturalist to the Challenger Expedition Commission from 1882 to 1884. In 1884 he was appointed Prosector, responsible for preparing dissections of animals that had died, at the Zoological Society of London. He became a leading authority on annelids, including earthworms.
4. A red British Museum crown stamp appears just below the signature.
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