Arachnoidiscus deficiens, unknown mounter

Arachnoidiscus deficiens

Arachnoidiscus deficiens from Jackson’s [Paddock], Dr Watts excavation, Oamaru, New Zealand. Unknown mounter. Mounted in Sirax and dated 29/10/[19]39. Olympus BHB microscope using 365nm LED light. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Abbe condenser, oil immersion. 2.5x Nikon CF PL photoeyepiece, removed 11mm of extension tube to increase the field of view. Monochrome converted Nikon d850 camera. 21 images stacked in Zerene (Pmax).

The ‘Dr Watts’ could be Morris Netterville Watt (1892-1973), who was an international expert on diatoms, and was awarded a Fellowship of the Royal Microscopical Society.