Hamilton.

you get a pale brick reaction that becomes more of a red-brown or brown-red with time. In wet weather, sometimes making a slit or two in the cap with a thumbnail will show a quick flash of pink; however, this made away and then be followed by the darker, brick-like colors. Brick staining is characteristic of several of the North American amidellas. The weakest staining/bruising reactions (very weak and often not pinkish) that I know of are in A. peckiana and A. whestoneae.

Very best,

Rod

Since yesterday, the floccose material on the stipe has turned pinkish.

Is the top of the stem MUCH more floccose that the already floccose parts we can see in the pictures? [Oh, I see the answer in the third picture.] I think this is an Amanita, and it belongs in Amanita section Amidella. Guessing at amidellas from pictures is hard to do, but I think there’s about a 75% chance of this being either A. volvata (if VERY DENSELY FLOCCOSE on the stem up under the cap) or a rather large specimen of A. pseudovolvata (if there is not a distinct increase in floccose material under the cap). [Added later: This is probably A. pseudovolvata. The top of the stipe is not like that in a young, fresh A. volvata. Also, the marginal striations on the cap are more pronounced in a young pseudovolvata (as here) than in volvata.]

Amanita section Amidella has an appendiculate margin (goop hanging from the edge, at least when young) as in sect. Lepidella and, in addition, the amidellas have a striate cap margin, almost always many squarely cut-off (truncate) short gills [pbreaks the supposed rule for amyloid spores going with attenuate (more or less gently narrowing) short gills], a totally elongating stem (as in inamyloid sections Vaginatae and Caesareae), and a multiply layered and robust volval sack.

Very nice, diagnostic pictures.

Very best,

Rod