A HISTORY OF STAFFORDSHIRE 



Lecidea uliginosa, Schrad. 



coarctata, Sm. 



rivulosa, Ach. 



contigua, Fr. 



f. leprosa (Leight.) 

 f. flavicunda (Ach.) 



calcivora, Ehrh. 



canescens, Dicks. 



myriocarpa, DC. 



alocizoides, Leight. 



chalybeia, Borr. 



grossa, Pers. 



caeruleonigricans, Light. 



denigrata, Fr. 



tricolor, With. 



Ehrhartiana, Ach. 



diluta, Pers. 



Caradocensis, Leight. 



- incompta, Borr. 



- alboatra, Hoffm. 



f. epipolia (Ach.) 



- aromatica, Sm. 



- carneo-lutea, Turn. 



- umbrina, Ach. 



pachycarpa, Dur. 



- milliaria, Fr. 



- sabuletorum, Flk. 



- premnea, Ach. 



- carneola, Ach. 



- endoleuca, Nyl. 



rubella, Ehrh. 



geographica, L. 



- petrza, Wulf. 



- concentrica, Dav. 



- cupularis, Ehrh. 



- trucigena, Ach. 



- Parmeliarum, Smrf. 



- parasitica, Flk. 



Opegrapha herpetica, Ach. 

 /. rubella (Pers.) 

 /. rufescens (Pers.) 



atra, Pers. 



Turneri, Leight. 



varia, Pers. 



/. notha (Ach.) 

 f. diaphora (Ach.) 



vulgata, Ach. 



Leightonii, Crombie 



lyncea, Sm. 

 Stigmatidium crassum, Dub. 

 Arthonia lurida, Ach. 



astroidea, Ach. 



Swartziana, Ach. 



pruinosa, Ach. 

 Graphis elegans, Sm. 



scripta, Ach. 



var. serpentina (Ach.) 

 var. pulverulenta (Ach.) 



inusta, Ach. 



sophistica, Nyl. 

 Endocarpon miniatum, L. 



hepaticum, Ach. 

 Verrucaria epigea, Ach. 



Dufourei, DC. 



nigrescens, Pers. 



glaucina, Ach. 



- viridula, Schrad. 



rupestris, Schrad. 



conoidea, Fries 



gemmata, Ach. 



epidermidis, Ach. 



- biformis, Borr. 



- chlorotica, Ach. 



f. trachona (Tay.) 



nitida, Weig. 



THE FRESHWATER ALG^ 



The freshwater algas are universally distributed and are to be 

 found in every situation where moisture exists, amid the most deleterious 

 surroundings or where the atmospheric conditions are good and health- 

 ful ; ' on damp walls and palings, on soil heaps, damp earth, pathways, 

 roadsides ; on wet rocks, stones in streams, in every ditch and water- 

 course ; in canals, ponds, and attached to the various aquatic plants 

 therein, in puddles, and the hoof holes of cattle in boggy places,' etc. 

 The green dust-like growth on tree trunks, palings and old walls is one 

 of the lower forms of alga?, Pleurococcus vu/garis ; in nearly every ditch 

 one or other species of Vaucheria may be found ; old canals are frequently 

 covered with the yellowish green masses of Enteromorpba intestinalis, and 

 many of the old clay holes in the coal districts are rich in species of 

 Nostoc and Conferva. The bogs, pools and watercourses of the Cannock 

 district yield many of the more rare and beautiful species, as Chcetophora 



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