It's the 100th anniversary of the sending of this 'Microfossil Christmas Card' by Arthur Earland (1866-1958) to his collaborator Edward Heron-Allen (1861-1943). The specimens are tiny fossils called Foraminifera – single-celled organisms that typically form shells of calcium carbonate with one or more openings. Most of them require a microscope to see fine details but others are clearly visible with the naked eye.
This 1909 slide features sandy looking lettering made mainly from tube-shaped Foraminifera that gather fine sediment from the sea floor to create a shelter for the organism. The initials 'E.H-A' represent the recipient Edward Heron-Allen. The specimens were taken from the Goldseeker oceanographical expedition which ran from 1902-1922 around Scotland.
Christmas greetings in 1921 from Arthur Earland, presumably to Edward Heron-Allen. Specimens for slides like these were often chosen for their aesthetic beauty and to show the range of shell morphologies created by the Foraminifera. The circular arrangements are about the size of a thumbprint.
This slide was sent in September 1922 at around the time Heron-Allen and Earland published their monograph on the Foraminifera found during Robert Scott’s ill-fated Terra Nova Expedition to the South Pole. Earland may well have been expressing his gratitude to Heron-Allen for all his help in getting the work published.
This Christmas slide bears the inscription 'Greetings from Eugene Xmas 1928'. Eugene was Heron-Allen’s nickname for Arthur Earland, while Earland’s nickname for Heron-Allen was 'Ned'.
This slide is made from specimens collected off the Canary Islands during the Challenger Expedition (1872-1876). Challenger was the first true oceanographic voyage – prior to this, the ocean bottom was completely unstudied.
Made by Heron-Allen, this is perhaps not the most beautiful slide in the collection. However, the back of the slide states that the pioneering Scottish oceanographer and marine biologist, Sir John Murray, was killed in a car crash shortly after handing Heron-Allen the sample from which this slide was made. Murray was responsible for editing and publishing over 50 volumes of reports describing the findings of the Challenger Expedition.
This arrangement was made in 1914 from beach sand collected at La Rochelle, France by Heron-Allen while researching for the biography of the famous French scientist Alcide d’Orbigny. D’Orbigny first became interested in Foraminifera while living there and published the first classification of the group in 1826.
These microfossils are from the West Indies. It's amazing that virtually none of the specimens have come loose despite many of them being over 100 years old. Arthur Earland used a mixture of gum tragacanth, alcohol, cinnamon and drop or two of thymol or clove oil to prevent the slides from attracting mildew. Each specimen was arranged and glued into place using a fine paintbrush.
This 1930 slide from Earland to Heron-Allen contains fewer specimens than some of the earlier ones. In the early 1930s the two scientists fell out, so this smaller arrangement may represent their waning relationship. Suggested reasons for their fall out include ill health, arguments over the authorship of a paper, scientific jealousy and possibly even a shared love interest.
These beautiful arrangements of microfossils were sent as Christmas cards by Arthur Earland (1866-1958) to his collaborator Edward Heron-Allen (1861-1943), both working at what was then the British Museum of Natural History.
All images were kindly provided by London's Natural History Museum, with captions supplied by the museum's microfossil curator, Dr Giles Miller. To read more about Earland and Heron-Allen, their Christmas cards and their sudden falling out, click here.