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NOTEWORTHY LECIDEACEAE FROM KNOX COUNTY, MAINE 



[Concluded] 

 G. K. Merrill 



Lecidea sylvicola Flot. Lich. Siles. No. 171. (1829). 



Thallus effuse, very thin, granulate, commonly dusky-gray, or at times 

 ■obsolete. Apothecia small, scattered or congregated, black, opaque, plane, 

 with an inconspicuous margin, or convex and immarginate. Spores 8, ellipsoid, 

 6-10 X 3-4.5 ju, hymenium bluish, hypothecium black or dark brown, para- 

 physes distinct, compacted, the tips dark bluish or greenish. 



On mica-schist in unshaded pastures, Rockport; granite and dead wood. So. 

 Thomaston. 



Dr. Fink, in Lichens of Minnesota, p. 74, finds it difficult to separate the 

 present from Biatora myriocarpoides (Nyl.) Tuck. It is possible to go further and 

 assert that the two species are identical with Lecidea cyrtidia Tuck., for it is 

 only occasionally that the latter affords characters making for separation. Dr. 

 Fink states that he finds Biatora myriocarpoides occurring on rocks in Minne- 

 sota, but that the specimens when submitted to Dr. Hedlund were pronounced 

 representative of Lecidea sylvicola. An abandoned granite quarry in So. Thomas- 

 ton recently furnished to the writer curious evidence of an identity between 

 the two species. On a heap of broken rock covered with L. sylvicola, a rotten 

 plank was found that bore in patches over its whole upper surface what, in the 

 absence of the rock lichen beneath, one would call perfectly good Biatora myriocar- 

 poides. The two plants were absolutely in agreement both internally and 

 externally. It is, however, very doubtful if Biatora myriocarpoides of 

 Tuckerman's Synopsis is in exact agreement with Nylander's Lecidea myrio- 

 carpoides, and for the present it is preferred to ally the lignicoline So. Thomas- 

 ton form with the associated Lecidea sylvicola. 



Lecidea crustulata forma geographica Cromb. Mon. Brit. Lich. Pt. II, 

 p. 71. (1911). 



On a rock, Warren, and on ledges, Rockport. 



Thallus decussated by dark hypothalline lines, but otherwise not differing 

 from the species. Previously unrecorded for America. 

 Lecidea goniophila (Flk.) Schaer. Enum. p. 127. (1850). 



Thallus effuse, leprous, cinereous, or at times subevanescent. Apothecia 

 small, scattered or aggregated, plane or convex, with a thickened and obtuse 

 margin, disk naked and black. Spores 8, elHpsoid, 10-14 ^ 5~9 M, hypothecium 

 colorless or faintly fuscescent, paraphyses distinct, compacted, tips more or less 

 colored and sometimes blackish. 



On flat-topped boulders by the roadside, Camden and Warren. 



The description of this species is that of Biatora pungens Koerb., given by 

 Nylander in Flora 1878, p. 248, as a synonym. L. goniophila is reported from 

 Minnesota by Dr. Fink, but the description in his work on the Lichens of Minne- 

 sota fails to fit the plant as here affirmed. Dr. Fink states that Hedlund deter- 



