Aphid head cross section
I collected a petiole gall from a yet to be identified tree. On cutting the specimen prior to fixing, I found it full of aphids (Pemphigus spp.) in an immature state. The aphids had wings, however, they could not survive outside the gall even long enough to get a photograph. On preparing the histological cross section of the gall, many of the aphids went along for the ride. This is a very opportunistic frontal plane section of an immature aphid showing the head. Of particular interest is the cross section of the two compound eyes showing the retinal cells and the lenses.
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:paraplast 3:1, 1:1, 1:3 1 hour each. Infiltrated in xylene saturated with Paraplast for 10 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 10 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min 2X. Cleared 2X xylene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope using an original magnification of 430X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.
Aphid head cross section
I collected a petiole gall from a yet to be identified tree. On cutting the specimen prior to fixing, I found it full of aphids (Pemphigus spp.) in an immature state. The aphids had wings, however, they could not survive outside the gall even long enough to get a photograph. On preparing the histological cross section of the gall, many of the aphids went along for the ride. This is a very opportunistic frontal plane section of an immature aphid showing the head. Of particular interest is the cross section of the two compound eyes showing the retinal cells and the lenses.
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:paraplast 3:1, 1:1, 1:3 1 hour each. Infiltrated in xylene saturated with Paraplast for 10 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 10 s. Water rinse 1 min. Stained 1 % aq. Erythrosin-B 2 min. Dehydrated 99 % IPA 2 min 2X. Cleared 2X xylene 5 min each. Mounted with DEPEX.
Photographed on a Spencer 42 petrographic polarizing microscope using an original magnification of 430X, using a Sony NEX 5N with a Leica MIKAS 1/3X adapter.