Radulum Ballouii is a novelty from several points of view. It is 

 a Radulum in the Friesian definition, accepted by everybody but 

 Mr. Banker, with teeth not awl-shaped, as in Hydnum, but obtuse, 

 tubercular. Fries knew only resupinate species, but an American, 

 pileate species, Radulum pallidum, has since been named; and 

 Radulum Ballouii is the second pileate species of Radulum known. 

 Then Radulum Ballouii has hard and woody texture, and I believe 

 in time will prove perennial. But one other ligneous Hydnaceous 

 plant is known, viz., Hydnofomes tinctorius, and the best classifica- 

 tion probably would be to put these two species together in one 

 genus. Then again Radulum Ballouii impresses me as most peculiar 

 in its habits. It grows on the living branches near the top of the 

 tree, and, as far as I can note from the specimen I have, it does not 

 attack the wood. I would not state that it is an epiphyte, but it 

 looks that way. 



Mr. Ballou found the plant abundant, and at first supposed it 

 to be a destructive parasite. In a recent letter to me he is inclined 

 to doubt the latter. When growing, the teeth are "golden yellow," 

 but no indication of the color remains on the dried specimens. When 

 old, the plants loosen and fall away from the limbs. It is curious 

 that no one found this unique fungus before, but its habitat, near 

 the tops of the trees, and the difficulty of access to the white cedar 

 swamps no doubt account for it. 



POLYSTICTUS BLUMEI (Fig. 770), FROM J. UMEMURA, 

 JAPAN. Pileus sessile, dimidiate, rigid, thin, pale, white when fresh. 



Fig. 770. 

 Polystictus Blumei. Showing pores, habits, and pores enlarged six diameters. 



563 



