Cortinarius Atkinsonianus Kauffman

"To professor G. F. Atkinson, whose enthusiasm in this phase of botany is well known, I owe the inspiration to take up and continue the study." - C. H. Kauffman, 1905

Cortinarius Atkinsonianus was described by Calvin Henry Kauffman in 1905. The species was described in Kauffman's article "The genus Cortinarius: a preliminary study" in the Bulletin of the Torrey Botanical Club, Volume 32 (6). The holotype description is found on page 324 and reads as follows: "Pileus 8 cm, broad, expanded, wax-yellow or gallstone-yellow to clay-colored and tawny (Ridg.), colors very striking and sometimes several present at once, viscid, smooth, even, somewhat shining when dry. Flesh thick, except at margin, blueish-white like the stem, or paler, scarcely or not at all changing when bruised. Gills comparatively narrow, 6-8 mm., width uniform except near outer end, adnate becoming slightly sinuate, purplish to yellow, then cinnamon. Stem violaceus-blue, 8 cm. long, 12-15 mm. thick, equal or slightly tapering upward, bulbous by a rather thick, marginate bulb 3 cm. thick, hung with the fibrillose threads of the universal veil, which is a beautiful pale-yellow and clothes the bulb even at maturity; violaceus blue within, solid. Spores 13-15 μ x 7-8.5 μ, very tubercular. The nature of the universal veil indicates its position in the subgenus Telamonia, but the viscid cuticle bars it. It needs further study. Only a single, rather mature specimen was found, among hemlocks and poplars, at the base of a sassafras sapling, Enfield Gorge, near Ithaca, N.Y., September 14, 1903, C. H. Kauffman." Its not clear whether the holotype collection survived. It is not present at the University of Michigan Herbarium, and does not appear to be at Cornell or the New York Botanical Garden according to the MycoPortal database. The University of Michigan Herbarium (MICH) has 17 collections of this species, including 4 Kauffman collections. MICH also has Kauffman's hand-written note cards for 5 collections of this species, as well as additional photographs and paintings. These are detailed below.

-Figure contained in the 1905 article describing Cortinarius Atkinsonianus.

In addition to the published holotype image ("Figure 6" shown above), there are 4 other photographs at MICH of the 1903 collection.

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There is also Kauffman's index note card with his macro- and microscopic description of the type collection (front and back), as well as his watercolor painting of the specimen.

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In the 1905 paper, Dr. Kauffman provides a partial key to the Cortinarii in the vicinity of Ithaca, N. Y. The path to Cortinarius Atkinsonianus yields the following description: "Pileus with a gelatinous cuticle, more or less viscid or glutinous when moist, as is also the stem in some species. [Myxacium and Phlegmacium.] Pileus not corrugate. Taste not very bitter. Spores large, 10 to 16 μ long. Stem bulbous or short. Spores 13-16 μ long; stem violaceus to blue."

The 1917 collection from Leal, Colorado (MICH 215236) has a note card shown below (front and back) that also references a collection made 5 days prior in the same locality. It says "same as painted Aug 24, 1917."

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Kauffman made a collection of Cortinarius Atkinsonianus 5 days prior to the previously listed collection in Leal, CO. The collection does not appear to be present at MICH, but there is an index card as well as the watercolor painting referenced in the August 29th collection.

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There is a 5th Kauffman note card for Cortinarius Atkinsonianus. This is a collection made October 20th, 1906 by Dr. O. E. Fischer in Detroit, Michigan. The collection doesn't appear to be present at MICH under this determination. The only Fischer collection at MICH of Cortinarius from that day and location is a collection of Cortinarius deceptivus (MICH 216093).

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The AHS#15398 collection from Ann Arbor, Michigan (MICH 215232) has a note card shown below (front and back).

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The AHS#15337 collection from Ann Arbor, Michigan (MICH 215234) has three images shown below.

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In a 1942 paper, Dr. Smith provides a revised key to the North American Species of Bulbopodium. The path to Cortinarius Atkinsonianus yields the following description: "Lamellae (and at least the apex of the stipe) at first violet purplish, blue or shades of these colors. (C. Atkinsonianus and C. cedretorum with yellowish gills are included here, as is C. arenicola with pallid gills). Lamellae not turning purplish when bruised. Spores averaging more than 10 μ long. Surface of pileus smooth or slightly uneven. Pileus if violet or purplish quickly changing to some other color. Pileus normally 6-12 cm broad. Spores averaging more than 12 μ long, surface of pileus yellow. Context deep violet, pileus and universal vale bright olive yellow."

The second collection I made, from Ann Arbor Michigan, is currently being accessioned at MICH. This page will be updated with the catalog number when one is assigned. The morphology of this collection matches pretty well with the description of this species. The purple colors were not as profound as my Wisconsin collection, but were still present. I do have a spore print for this collection, it was the typical Cortinarius rusty-brown. I examined the spores under a microscope and they were tubercular and the sizes were exactly as described by Kauffman. There are a few more images with different exposure, please contact me for more information.

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