168 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM, 
to olivaceous-brown or blackish, beneath usually darker, papillose and reticulated with 
perpendicular and horizontal plates of supporting tissue; apothecia commonly in 
groups, these raised, black and rounded or irregular in outline, convex, 0.75 to3 mm. in 
diameter, the apothecia of a group often more numerous than in the last and of about 
the same size and form; hypothecium pale-brownish or darker; hymenium pale- 
brownish or pale; paraphyses simple or rarely branched, the apex commonly thickened 
and brownish; asci clavate; spores hyaline or pale, oblong, 11 to 13 pe long and 4 to5 pz 
wide. 
Frequent in the northern portion of the State. On rocks. 
Distributed throughout the Northern States and British America. Also known in 
South America and northern Europe. 
Umbilicaria muhlenbergii of the preliminary reports. 
3. Gyrophora vellea (L.) Ach. Meth. Lich. 109. 1803. 
Lichen velleus L. Sp. Pl. 1150. 1753. 
Thallus smooth above, variously rounded or irregular in form, the margin usually 
more or less torn and irregular, rather large-sized, 6.5 to 25 em. in diameter, consid- 
erably thicker and stronger than the two above described, ash-color above, below 
brown or blackish and clothed with strong rhizoid-like cilia; apothecia commonly in 
groups, these raised, convex, usually rounded and black, the few seen 1 to 3 mm. in 
diameter, the individuals frequently much elongated and quite as numerous in the 
groups as in the last; hypothecium dark brown or rarely paler; hymenium pale or 
brownish; paraphyses simple or branched, the apices frequently enlarged and brown- 
ish; asci cylindrico-clavate; spores hyaline or pale, ellipsoid, 8 to 12 long and 5 to7 pz 
wide. Seldom fruited. 
The plant has about the same distribution in the State as the last, but is by no means 
so common. On rocks. 
In the United States, confined for most part to mountains and to cold shores, but more 
common throughout British America. Known also in South America and Europe. 
Umbilicaria vellea of the preliminary reports. 
4. Gyrophora dillenii (Tuck.) Arn. Oesterr. Bot. Zeitschr. 1896: 16. 1896. 
Umbilicaria dillenit Tuck. Syn. Lich. N. E. 72. 1848. 
Thallus smooth above, irregular in form, and margin much as the last, but the thallus 
brown and varying toward dark or ashy-brown, never ash-colored, beneath also much 
as the last, but on the whole of a deeper black, 7 to 32.5 em. in diameter (our largest 
species); apothecia usually in convex, more or less orbicular groups of the same 
general form as in the last, the groups sometimes exceeding 4 mm. in diameter; spores 
ellipsoid, pale or hyaline, 17 to 25 4 long and 9 to 15 » wide. 
The apothecial and spore characters are taken from Tuckerman, our plant being 
almost always sterile and no well-fruited specimens being at hand. 
Distributed throughout the extreme northern portion of the State and extending 
as far south as Taylors Fallsalong the eastern boundary. On rocks. 
A strictly North American plant distributed throughout the Atlantic States, though 
confined to the mountains toward the south. More common throughout the eastern 
portion of British America. 
Umbilicaria dillenii of the preliminary reports. 
UMBILICARIA Hoffm. Descr. Pl. Crypt. 1:7. pl. 2. f. 1-4. 1790. 
The thallus is foliose and, like that of Gyrophora, is attached to the substratum by 
an umbilicus. The lower cortex is thickened as in Gyrophora, for the same purpose, 
that of support, and the upper cortex is likewise thin. In our species at least, the 
mechanical plates are wanting and seem to be replaced by the rings of tissue about 
the pustules. The algal symbiont is Cystococcus. 
