BOTANY 

 THE LICHENS (Licbenes] 



Very little is known as to the distribution of the lichens in War- 

 wickshire. The records of the elder botanists are few, are in some in- 

 stances doubtful, and can rarely be received with confidence, except 

 when they treat of the more readily recognized species. The natural 

 and artificial conditions prevailing in the county are not indeed favourable 

 to a rich lichen flora. Lichens naturally depend on light and pure 

 atmospheric surroundings for their existence or full development ; and 

 being of slow growth they cannot attain maturity under conditions of 

 frequent interference, from the surface alterations that are inseparable 

 from thickly-populated manufacturing districts. In a contaminated 

 atmosphere or in shady crevices these plants will not come to perfection, 

 but will assume the form of a Lepraria, which is an abnormal condition 

 of many of the lichens. The yellow powdery and white patches com- 

 mon on *oaks are examples of this state. Still in those portions of the 

 county remote from large towns many of the more common species 

 occur in abundance. On the trees a rich growth of Ramalina fraxinea, 

 Parmelia caperata and Physcia ciliaris ; on heathy footways tiny forests of 

 Cladonia pyxidata or C. cornucopioides ; on the stone coping of walls and 

 bridges grey masses of Lecanora atra or Lecidea lucida ; in damp woods 

 Cladonia digitata or the more common Peltigera canina ; on old palings 

 Parmelia olivacea and Usnea barbata, and on old walls and slated roofs the 

 golden fronds of Physcia parietina, every sort and condition of habitat 

 being the home of one or other of the lichens. The following list is an 

 incomplete record of the Warwickshire lichens : 



Collema crispum (Huds.) 



nigrescens (Huds.) 

 Leptogium lacerum (Ach.) 



- fragrans (Sun.) 

 Sphinctrina turbinata (Pers.) 



- anglica (Nyl.) 



Calicium phaeocephalum (Borr.) 



- trichiale (Ach.) var. ferrugineum 



(Borr.) 



- hyperellum (Ach.) 



- trachelinum (Ach.) 



- quercinum (Pers.) 



- curtum (Borr.) 



subtile (Pers.) 

 Coniocybe furfuracea (Ach.) 

 Trachylia tympanella (Fr.) 

 Cladonia cervicornis (Schar.) 



- alcicornis (Flk.) 



pyxidata (Fr.) 



var. fimbriata (Hoffm.) 



furcata (Hoffm.) 



squamosa (Hoffm.) 



cornucopioides (Fr.) 



digitata (Hoffm.) 



var. macilenta (Hoffm.) 

 Cladina sylvatica (Hoffm.) 



Cladina rangiferina (Hoffm.) 



- uncialis (Hoffm.) 

 Stereocaulon paschale (Ach.) 

 Usnea barbata f. florida (L.) 



/ hirta (L.) 



f. plicata (L.) 

 Alectoria jubata (L.) 



lanata (L.) 



Evernia furfuracea (Mann.) 



prunastri (L.) 

 Ramalina farinacea (L.) 



fraxinea (L.) 



fastigiata (Pers.) 

 Cetraria aculeata (Fr.) 

 Platysma glaucum (L.) 

 Peltigera canina (L.) 



rufescens (Hoffm.) 

 Stictina scrobiculata (Scop.) 

 Sticta pulmonaria (Ach.) 

 Parmelia caperata (L.) 



olivacea (L.) 



physodes (L.) 



ambigua (Wulf.) 



perlata (L.) 



tiliacea (Ach.) 



var. scortea (Ach.) 



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