An arrangement of five diatoms with the label ‘Nitzschia various new species’ and then added in pencil ‘pulcherrima in various new positions’. More on this in a minute. From Colon, Panama. Damage to the coverslip and mountant. Prepared by Arthur Charles Cole. Olympus BHB microscope using 450nm LED light. As well as the pair I imaged two at higher resolution. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Images stacked in Zerene (Pmax).
Nitzschia grandis Kitton, 1874. Original description: Kitton, F. (1874). New Diatoms. Monthly Microscopical Journal, 12: 218-220, pls 81-82. Page 219, Plate 82, Figure 5. Synonymised name: Homoeocladia grandis (Kitton) Kuntze, 1898. 63x Leitz Pl Apo NA 1.4 objective, oil immersion. 11mm removed from the tube the camera to increase the field of view. 42 images stacked. I am reasonably confident of this ID, but will leave it with a question mark for now.
Perrya pulcherrima Kitton. Original description: Kitton, F. (1874). New Diatoms. Monthly Microscopical Journal, 12: 218-220, pls 81-82. Page 218, Plate 81, Figures 1-3. Synonymised name: Homoeocladia pulcherrima (Grunow ex Kitton) Kuntze, 1898. Also mentioned as being known as Nitzschia pulcherrima Grunow. See discussion in Mann, D.G. (1978). Studies in the Nitzschiaceae (Bacillariophyta). Vols 1 & 2. xxxiii + 386 pp. + 146 plates. Ph.D. Dissertation. University of Bristol. Chapter 4, Section 4.6.6.5 for a discussion on Perrya. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. 46 images stacked. I am confident enough with this to not need a question mark.