Here are some of the formidable weapons on the rear appendages of the Corycaeus mentioned above. So if you are a suitable meal, and it sees you with those big eyes, this is what you deal with next!

Olympus BHS. Olympus 60/1.40 S Plan Apo. Olympus NFK 1.67x photoeyepiece.DIC illumination with electronic flash. Canon 50D.

Here is a Diaptomas. While I think I prefer the brightfield version of one photographed last June, darkfield is always interesting. (And the antennae are always impressive to see).
Olympus BHS. Olympus 10/0.40 S Plan Apo. Olympus NFK 1.67x photoeyepiece. Darkfield illumination with electronic flash. Canon 50D.

Here are some diatoms. Upper is darkfield with 10X, lower is oblique brightfield with 20X.

