A photogram of Algae, made by Anna Atkins as part of her 1843 book, Photographs of British Algae: Cyanotype Impressions, the first book composed entirely of photographic images.

At http://digitalgallery.nypl.org/nypldigital/id?419608 as retrieved 12 August 2009, the image details are as follows:

• "Image Title: Dictyota dichotoma, in the young state; and in fruit."
• "Creator: Atkins, Anna, 1799-1871 -- Photographer"
• "Additional Name(s): Herschel, John F. W. (John Frederick William), Sir, 1792-1871 -- Former owner"
• "Published Date: 1843-53"
• "Medium: Cyanotypes"
• "Specific Material Type: Photographs"
• "Item Physical Description: 1 photograph"
• "Source: Photographs of British algae: cyanotype impressions. / Part XI."
• "Source Description: 231 photographs and 2 manuscripts and 1 portfolio"
• "Location: Stephen A. Schwarzman Building / Spencer Collection"
• "Catalog Call Number: Spencer Coll. Eng. 1843 93-440"
• "Digital ID: 419608"
• "Record ID: 103412"
• "Digital Item Published: 3-31-2004; updated 2-12-2009"