Darvin- Thanks for pursuing this. Would you mind writing a summary and adding it to the Notes for the Lactarius rufulus name?
Hesler and Smith used the original description by Peck for the macrocharacters and the type specimen for obtaining the microcharacters when they published “North American Species of Lactarius” (page 512). They also tapped Harry Thiers for a description of fresher material and printed his description (page 513). Methven’s description seems to follow Hesler’s and Arora’s seems to follow Thiers. Harry Thiers even noted the “tingling” on the tongue! Dr. Thiers and Arora are describing the species I collect, so I think Methven made an error in his work and since Peck was using dried material sent from Stanford University the odor, taste and type of latex (color) could easily have been compromised compared to fresh material. The best printed description is in Arora and both of his books have the only photographs of what I’m calling the “Southern California Candy Caps”.
Mushrooms Demystified is what I used. After reading Methven, I will pay attention to latex color and taste. I recall some of these in the past had whitish latex with “chunks” of very white particles in them.
I’ve pretty much stopped using L. rufulus since Methven in Agaricales states that it has white (not whey-like) latex, no odor and an acrid taste. Arora’s definition is a bit broader. I used to use L. rufulus for the larger, more mildly scented collections of L. rubidus that I would see fairly regularly in the Santa Cruz area and are quite common in southern California, but since reading Methven, I haven’t found any that I would apply L. rufulus to.