Equistetum sp. strobilus
Transverse section of a Equistetum sp. strobilus (spore producing structure). The strobilus as found is shown at: www.flickr.com/photos/14643312@N02/18511410355/. Equistetum or Horsetail is a vascular plant which produces spores instead of seeds. The sporangiophore is shown at the left. It consists of 3 sporangia in which the spores (dark stained circles) are produced. The stem is at the left where the vascular bundles are clearly evident. The specimen is from the edge of the Dowagiac River.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 24 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Paraplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in Xylene 2X, 10 min each. Rehydrated 99 (10 min), 90 (10 min.), 85, 70 % IPA, 2 min. each. Stained Gill's Hematoxylin 20 sec. Washed 3 min running water. Blued 0.05 % lithium carbonate 3 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min 2X. Cleared 2X xyene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope using an original magnification of 30X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.
Equistetum sp. strobilus
Transverse section of a Equistetum sp. strobilus (spore producing structure). The strobilus as found is shown at: www.flickr.com/photos/14643312@N02/18511410355/. Equistetum or Horsetail is a vascular plant which produces spores instead of seeds. The sporangiophore is shown at the left. It consists of 3 sporangia in which the spores (dark stained circles) are produced. The stem is at the left where the vascular bundles are clearly evident. The specimen is from the edge of the Dowagiac River.
The protocol was as follows. Specimens fixed in FAA (formaldehyde, acetic acid, ethanol) 24 hr. Dehydrated in 35, 50, 75, 85, 95, 99 % IPA in water, 6 hours each min. Infiltrated in xylene saturated with Paraplast for 2 days, followed by 2 changes of melted Paraplast for 2 hours each. Embedded in Paraplast. Sectioned on a Spencer 820 microtome at 11 micron. Cleared in Xylene 2X, 10 min each. Rehydrated 99 (10 min), 90 (10 min.), 85, 70 % IPA, 2 min. each. Stained Gill's Hematoxylin 20 sec. Washed 3 min running water. Blued 0.05 % lithium carbonate 3 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min 2X. Cleared 2X xyene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope using an original magnification of 30X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.