Everyone likes a mystery and this is one that I discovered recently. While looking through the Haddon Collection at the Horniman Museum , I came across a card with a drawing of a sea anemone (see below left). Earlier in the Collection, I had been looking at the original paintings by Philip Henry Gosse for Plate V of his book Actinologia Britannica, a comprehensive guide to sea anemones and corals found around the British coast. Close examination of the sea anemone illustrated on the card, especially its shape, colour and arrangement of the tentacles, made me think that this must be the basis for the watercolour that was used for the Plate (below right).
Let's get some more information on the card (shown below in more detail). The drawing has been overwritten by the address and also the term "Picture", both written in ink and apparently in the same handwriting. There is also writing in pencil: "Aiptasia amacha" at the top; "See Pl. V" at bottom right; "44" at top right; and at bottom left "tentacles light umber with pellucid dark centres. Column pale ochre". The card has three postmarks: one for North Queensferry (May 2nd); one indecipherable (May 3rd?); and one for Torquay (May 4th).
L. J. P. Gaskin (the Librarian of the Horniman Museum in the 1930s) identifies the descriptive pencil writing at the bottom left as that of Gosse and states that the drawing provides "A further link with the Actinologia" and was "probably the original of the figure [of Aiptasia couchii] in Plate 5 of that work" . The pencil marking to this effect on the card (presumably added by Haddon, together with the catalogue number 44) also supports this idea, yet the drawing is labelled "Aiptasia amacha".
This is what Gosse wrote about the material he used to illustrate A. couchii in Actinologia Britannica :
..In the latter part of March of the present year (1858), Dr Hilton of Guernsey found on the shores of that island, and kindly sent to me, several specimens of an Anemone new to him, and equally so to me.. ..I.. ..ventured to describe it under the name Aiptasia amacha..
..Subsequently, however, I have found that the species has been well described and figured by Mr. W. P. Cocks, in his valuable list of the Actiniæ of Falmouth, published in the Report of the Cornwall Society for 1851, under the title of Anthea Couchii, which specific name takes precedence of mine. It is true, in his description, mention is made of three white lines extending longitudinally up the column, of which no trace exists in my specimens; but by a coloured drawing with which Mr. Cocks has favoured me, I perceive that these lines were not equidistant and symmetrical, but all close together on one side; a circumstance which at once shows their presence to have been accidental, and of no value as a character, while in every other respect, even in the most minute points, his drawing and description agree with my specimens.
As the drawing on the card is labelled "Aiptasia amacha", and does not show evidence of any longitudinal lines on the column, it seems that this is indeed by Gosse and that explains its near identical appearance with the specimen shown in Plate V in Actinologia Britannica. So, why is the drawing overwritten with the address and the word "Picture"and who wrote the card? I cannot answer the first part of that question, nor the second. My first thought was that Cocks had sent the card, but the handwriting is rather different to many other examples of his (Michael Carver in pers. comm.) and this was probably not Cocks' drawing anyway. If we follow the sequence of postmarks, the card was sent from North Queensferry (the only place of this name being on the Firth of Forth, way outside the known range of A. couchii ) via a second destination and then sent on from Torquay to Gosse at Sandhurst, the villa where he lived in St Marychurch, a village within that town.
A mystery indeed.
 L. J. P. Gaskin (1937) On a collection of original sketches and drawings of British sea-anemones and corals by Philip Henry Gosse, and his correspondents, 1839-1861, in the Library of the Horniman Museum. Journal of the Society for the Bibliography of Natural History 1: 65-67
 Philip Henry Gosse (1860). Actinologia Britannica. A history of the British sea-anemones and corals. London, John Van Voorst.
I would like to thank the Horniman Museum for allowing me to view the Haddon Collection and to reproduce the illustrations in this post. Michael Carver, Judith Hann and the Royal Cornwall Polytechnic Society provided valuable insights into the work of W. P. Cocks and it is a pleasure to acknowledge their help.