A little bit of a frustrating slide this one. Described as ‘Aulacodisci‘ and ‘Important’ but the location has smudged out. Unknown maker. This has 7 Aulacodiscus species. No clue as to why it is ‘Important’. The smudged out location could (and I emphasize ‘could’ here) be Bains. U. which would correspond to Bains Upper in Oamaru, New Zealand. My attempts at naming are based on these being from Oamaru.
Olympus BHB microscope using 450nm LED light. The image of the arrangement was done with a 10x Nikon Plan Apo NA 0.45 objective, and brightfield lighting. Two stacks were prepared (Zerene, Pmax) and pasted together in Photoshop. Two diatoms where then selected for imaging at higher resolution.
Aulacodiscus sp. (A. intumescens?). Right hand block of 4, bottom left. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. 11mm spacer to the camera removed to fit the diatom in the image. Monochrome converted Nikon d850 camera. 105 images stacked in Zerene (Pmax). Top view with the rim down away from the coverslip. The identification as Aulacodiscus intumescens is based on the Oamaru Diatoms website (see here).
Aulacodiscus sp. (A. hustedtii?). Right hand block of 4, top right. 63x Leitz Pl Apo NA 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece.Monochrome converted Nikon d850 camera. 52 images stacked in Zerene (Pmax). underside view with the rim towards the coverslip. The identification as Aulacodiscus hustedtii is based on the Oamaru Diatoms website (see here).
Both of these are being left with a question mark for now.
I recently acquired about 60 slides by this maker, so if you want to see others by them, search for AAAAA in the Search option at the top of the page, and I’ll include this in each of the pages for them.