Colorado.

18a. Didymium anomalum Sturg.

[Plate XIX.], Figs. 13 and 13 a.

Sporangia in the form of very thin effused grey plasmodiocarps, 2–10 cm. long, 1 mm. or less in thickness. Wall single or membranous, hyaline or yellowish, with rather scanty deposits of small, stellately crystalline or amorphous lime. Columella none. Capillitium consisting entirely of straight membranous, tubular, columns, extending from the base to the upper wall of the plasmodiocarp, 7–22 µ thick and usually containing small crystalline masses of lime. Spores bright violet-brown, minutely and irregularly spinulose, 10–11.5 µ diam.

Hab. on the inner bark of Populus. Colorado Springs, Colo., July 1911.

Our specimens by the courtesy of Dr. Sturgis.

EXTRA-LIMITAL

18. Didymium intermedium Schroeter.