acidic rock. Collema conglomeratum Hoffm. [Collemataceae] Skorepa et al. (1979) – on bark. Collema furfuraceum (Arnold) Du Rietz [Collemataceae] Skorepa et al. (1977) – Allegany Co., on trunks of deciduous trees. Skorepa et al. (1979) – bark, acidic rock. E.G. Worthley Herbarium - Allegany Co., Terrapin Run, near base of tree trunk. Collema fuscovirens (With.) J.R. Laundon [Collemataceae] Syn.: Collema tuniforme (Ach.) Ach. Skorepa et al. (1979) – on calcareous rock. Collema leptaleum Tuck. [Collemataceae] Skorepa et al. (1979) – on bark. Collema subflaccidum Degel. [Collemataceae] Skorepa et al. (1979) – acidic rock. E.G. Worthley Herbarium - Baltimore Co., Gunpowder River, on bark of Tulip Tree. Collema undulatum Laurer ex Flotow [Collemataceae] Skorepa et al. (1979) – on acidic rock. Cyphelium tigillare (Ach.) Ach. [Caliciaceae] Skorepa et al. (1979) – on wood. Dactylospora inquilina Hafellner [Dactylosporaceae] Lendemer & Knapp (2007) - (5. Hickory Pt.) (on Pertusaria paratuberculifera) Dermatocarpon luridum (With.) J.R. Laundon [Verrucariaceae] Syn.: Dermatocarpon fluviatile (G. Web.) Th. Fr. Skorepa et al. (1977) – Baltimore Co., on rocks. Skorepa et al. (1979) – on acidic rock. E.G. Worthley Herbarium - Carroll Co., in stream bed; Frederick Co., on boulder in stream. E.C. Uebel Herbarium – Baltimore Co., Hollofield, on moist rock. Dermatocarpon miniatum (L.) W. Mann [Verrucariaceae] Skorepa et al. (1977) – Baltimore Co., on rock ledge. Skorepa et al. (1979) – on acidic rock, calcareous rock. E.G. Worthley Herbarium - Montgomery Co., Great Falls Dibaeis baeomyces (L. f.) Rambold & Hertel [Icmadophilaceae] Syn.: Baeomyces roseus Pers. Skorepa et al. (1977) – Harford Co., on rock ledge. Skorepa et al. (1979) – on soil. Biechele (2002) – lower eastern shore of Maryland. E.G. Worthley Herbarium - Lichens of Soldiers Delight; Howard Co. Dimelaena oreina (Ach.) Norman [Physciaceae] Skorepa et al. (1977) – Allegany Co., on sandstone outcrop. Skorepa et al. (1979) – on acidic rock. Diploschistes scruposus (Schreber) Norman [Thelotremataceae] Skorepa et al. (1979) – on acidic rock. Dirinaria frostii (Tuck.) Hale & Culb. [Physciaceae] Skorepa et al. (1977) – Allegany Co., on shale outcrops. Skorepa et al. (1979) – on acidic rock. Endocarpon petrolepideum (Nyl.) Nyl. [Verrucariaceae] E.C. Uebel Herbarium – Prince George's Co., Greenbelt, on hill of concrete (identified by Dr. Othmar Breuss, Vienna, Austria, Mar 2005). Endocarpon pusillum Hedwig [Verrucariaceae] Skorepa et al. (1977) – Washington Co., on chert. Skorepa et al. (1979) – on calcareous rock, cement. Ephebe lanata (L.) Vainio [Lichinaceae] Skorepa et al.