Pyrogram. Flash pyrolysis with gas chromatography mass spectrometry in the presence of tetramethylammonium hydroxide(Py-TMAH)-GC/MS profiles of (A) undigested softwood and (B) termite feces. (The peaks labeled as 1N to 25N in the fecal spectrum are novel pyrolyzed compounds that appeared after digestion by termites. All the peaks indicated in the undigested control spectrum are pyrolyzed compounds that were not present in the fecal sample. he structures of the labeled compounds are shown in Figure 5.