An arrangement of three Rhaphoneis amphiceros var. gemmifera from Lompoc, California, USA. Some other writing in pencil. Top label “See letter ??? 1920, amphiceros var. gemmifera Ehr.”. Bottom label “Perag 83, 11-14. Dr ???? material. 761. 13 (or B).”. Prepared by William Allott Firth. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 44 images Pmax.
Rhaphoneis amphiceros var. gemmifera (Ehrenberg) H.Peragallo & M.Peragallo 1901. Published in: Peragallo, H. & Peragallo, M. (1901). Diatomées marines de France et des Districts Maritimes Voisins. Atlas. pp. pls 81-96. Grez-sur-Loing (S.-et-M.): J. Tempère, Micrographe-Editeur. Plate 83, Figures 11–14. This is based on the pencil writing.