
20140612-DSLR_IMG_0034-Edit.jpg by pwnell, on Flickr
Aiptasia unfired nematocyst, 60x/1.2, DIC

20140612-DSLR_IMG_0138-Edit.jpg by pwnell, on Flickr
Aiptasia nematocysts and zooxanthellae, 60x/1.2, DIC, HF B

20140612-DSLR_IMG_0174-Edit.jpg by pwnell, on Flickr
Aiptasia fired nematocyst, 60x/1.2, DIC, HF B

20140612-DSLR_IMG_0235-Edit.jpg by pwnell, on Flickr
Mushroom unfired nematocysts, 60x/1.2, DIC

20140612-DSLR_IMG_0322-Edit.jpg by pwnell, on Flickr
Mushroom unfired nematocyst, 60x/1.2*1.25,DIC, HF A

Mushroom nematocysts by pwnell, on Flickr
Mushroom unfired nematocyst, 60x/1.2*1.25,DIC, HF A

20140612-DSLR_IMG_0499-Edit.jpg by pwnell, on Flickr
Mushroom unfired nematocyst, 60x/1.2*1.25,DIC, HF B

20140612-DSLR_IMG_0532-Edit.jpg by pwnell, on Flickr
Mushroom fired nematocyst, 60x/1.2*1.25,DIC, HF A+B

20140612-DSLR_IMG_0724-Edit.jpg by pwnell, on Flickr
Mushroom unfired nematocysts, 60x/1.2*1.25,DIC, HF A

20140612-DSLR_IMG_0785-Edit.jpg by pwnell, on Flickr
Mushroom zooxanthellae and nematocysts, 60x/1.3*1.25,DIC, HF A
Not a nice photo, but this gives you an idea of how long the thread of a mushroom mesenterial filament nematocyst is when triggered.

Mushroom triggered nematocyst, 10x*1.25, DIC, Pano of 2 photos stacked vertically.