118 
IOWA ACADEMY OF SCIENCES. 
89. Patellaria davispora (Peck) Sacc. 
Plants very small, black, when dry hysterioform, 
elongated, when wet becoming more or less expanded, 
older specimens often circular in outline; sporidia clavate, 
3 to 4-septate, brownish. This species has been found to 
be very common on decorticated willow and often on the 
bark. The plants, especially when young, resemble those 
of the genus Hysterium but when mature resemble more 
closely those of the genus Patellaria. Various collections, 
1902-5. Iowa City. Very common on willow. 
90. Lecanidion atratum (Hedw.) Rabenh. 
Plants small, black; hymenium nearly plane; sporidia 
hyaline, 7 to 10-septate; paraphyses bluish. On decorti- 
cated wood. Autumn, 1904. Iowa City. Rather common. 
91. Lecanidion tetraspora M. & M. 
Fatellaria tetraspora, Journal of Mycology 8, p. 180. 
Very closely related to the preceding but asci 4-spored and 
more cylindrical. Plants very small, black in mass, 
gregarious. On decorticated wood (ash ?). Autumn, 1904. 
Iowa City. Rather common. 
92. Blytridium fenestratum (C. & P.) Sacc. 
Plants small, black, circular in outline; hymenium 
almost plane; sporidia muriform. On poplar branches. 
Decorah, Iowa, August, 1882, E. W. D. Holway. 
FAMILY— CENANGIACE^. 
93. Cenangium popidueum (Pers.) Rehm. 
Plants breaking through the epidermis, caespitose, brown- 
ish, 5 mm. to 2 cm. in diameter. On dead branches of 
Poptdus tremiiloides and P. grandidentata. Howard county. 
B. Shimek;— Iowa City, April 13, 1905. Very abundant 
and common. 
94. Cenangium rubiginosum (Fr.) Sacc. 
On dead limbs of Carpinus americana. Decorah, Iowa, 
E. W. D. Holway. 
95. Dermatea cerasi (Pers.) Fr. 
Plants small, light colored externally; hymenium dark. 
On rotten wood. Iowa City. Rare. 
