FINK—THE LICHENS OF MINNESOTA. 61 
simple or rarely branched, frequently enlarged and darkened toward the apex; asci 
cylindrico-clavate or cylindrical; spores fusiform-oblong and frequently curved, 
4-celled, hyaline, 13 to 22 « long and 38 to 5 » wide. 
Once collected along the northern boundary at Emo, Ontario. On cedars. 
Elsewhere in North America in California, South Carolina, Alabama, and Ohio. 
Known also in Europe and Asia. 
This was determined by T. Hedlund as Lecanactis chloroconia Tuck., and the plant 
was so recorded in the seventh preliminary report. Tuckerman reduced his plant 
to a subspecies of the above species, but the spore measurements in our plant seem to 
connect it with the type rather than the subspecies. 
Family GYALECTACEAE. 
Like the last family, the present one is represented in our flora by a few very rare 
species. The three genera to which these belong show some external resemblance 
in the commonly urceolate disk, the proper exciple, and the usually evanescent thal- 
loidone. Indeed, Gyalecta and Secoliga are certainly closely related genera, as shown 
both in the thallus and in the apothecial characters. However, the stronger, dark 
proper exciple of Conotrema would seem to make its position in the family doubtful. 
But though the exciple sometimes nearly closes the disk, we can not think that the 
genus should be placed with the Pyrenulaceae. Yet it is readily admitted that the 
family, Gyalectaceae, is not a very natural one and that the genera might perhaps 
as well be parceled out to other families as is done by some authors. 
The thallus is crustose in all of our plants, but minutely foliose forms occur else- 
where. It is usually thin and granular and sometimes evanescent, so that the plants 
appear much like closely related fungal Discomycetes. This is especially true in the 
first two genera. The algal symbiont is at least commonly Cystococcus. 
The first two genera are also closely related as to spore characters, but here again 
Conotrema seems quite distinct. 
The genus Urceolaria, which we have placed with the Physciaceae, is frequently 
regarded as a member of the present family. 
While the family should, on the whole, doubtless stand next below the Lecideaceae, 
the poorly developed and usually evanescent thalloid veil or exciple seems to indicate 
a relationship with the Lecanoraceae. However, we must not lose sight of the fact 
that some of the Lecideaceae also show some hint of a thalloid exciple. 
GYALECTA Ach. Lich. Univ. 30, 151. pl. 7. f. 7-9. 1810. 
The thallus, in the American forms at least, is crustose and without a distinct cortex. 
The color is commonly sea green, varying toward greenish, ashy, or brownish. The 
structure is usually thin or very thin and variously smooth, chinky, granulate, leprose, 
or powdery, and frequently disappears. Some of the higher forms are said to possess 
upper and lower cortices, but we have not examined species having such layers. The 
algal symbionts are forms of Cystococcus, or according to some observers Chroolepus. 
The apothecia are commonly sessile and minute, though in a few species they may 
reach middle size. They are commonly more or less urceolate, and are uniformly 
surrounded by a somewhat colored proper exciple. Rarely a variously imperfect 
and more or less evanescent thalloid exciple surrounds the proper one. The hypothe- 
cium and the hymenium are commonly pale, and the paraphyses are usually simple, 
though compound ones may be found in some of the species. The asci vary from 
clavate to cylindrico-clavate. The spores are hyaline and 2-celled, though 4-celled 
species have commonly been admitted to the genus, and Tuckerman admitted even 
10-celled forms, which we place under Secoliga. 
The relations of the genus are very uncertain. The presence of the thalloid exciple 
in some species looks toward Lecanora; but such a structure also occurs in certain 
