MIDDLESEX FLORA. 169 



Nephroma, Ach. 



N. tomentosum, (Hoffm.) Koerb. 

 Waltham. 



N. Helveticum, Ach. 

 Chelmsford, Medford, Lexington, Natick. 



Peltigeea, (Willd., Hoffm.) F6e. 



P. aphthosa, (L.) Hoffin. 



Waltham (C. J. Sprague). 

 P. polydactyla, (Neck.) Hofiftn. 



Waltham. 

 P. rufescens, (Neck.) Hofiin. 



Cambridge, Waltham. 

 P. canina, (L.) Hoflfin. 



Waltham. 

 P. canina, (L.) Hoffm., var. sorediata, (Schaer.) 



Waltham. 



Physma, Mass. 



P. luridum, (Mont.) 

 Waltham. 



Pannabia, Delis. 



P. lanuginosa, (Ach.) Koerb. 



Waltham. 

 P. molybdea, (Pers.) Tuck., var. cronia, Nyl. 



Waltham. 



COLLEMA, Hoffm., Ft. 



C. verruciforme, Nyl. 



Cambridge. 

 C. flaccid um, Ach. 



Waltham. 



Leptogitjm, Fi-., Nyl. 



L. pulchellum, (Ach.) Nyl. 



Waltham. 

 L. Tremelloides, (L. fll.) Fr. 



Medford, Waltham, Nalick. 

 L. myochroum, (Ehi-h., Schaer.) Tuck., var. saturninum, 



Schaer. 



Chelmsford, Cambridge, Watertown, Waltham (Tuckerman). 



Placodium, (DC.) Naeg. & Hepp. 



P. elegans, (Link) DC 

 Cambridge. 



