VERRUCARIEiE. 49 



Sussex ! Mr. Borrer. Thringstone, Leicestershire ! 

 Rev. Churchill BaUngton. Breedon Hill, Leicestershire ! 

 Walls of Castle Farm, Pulley, near Shrewsbury, Shrop- 

 shire ! 



Thallus thick, crustaceous, olive-tawny, very much 

 cracked, areolae rather large, somewhat rugged, or raised 

 into small irregular warts or scaly elevations. Apothecia 

 tolerably large, one or several immersed in each areola, 

 black, the apex more or kss prominent. Perithecium 

 entire, black ; nucleus white. The crust of the thallus 

 being of an uniform texture, without any black sub- 

 stratum, and the cracks separating the areolae conse- 

 quently deep and empty, prevent this from being con- 

 founded with V. polystida, which grows in similar 

 situations on old walls. It has doubtless been passed 

 over as a variety of V. nigrescens, from which the struc- 

 ture of the thallus and perithecium separate it. 



22. V. poLYSTicTA, Borr. Sporidia in asci 8, narrow- 

 oblong, margined, pale-yellow. Plate XXL fig. 5. 



Verrucaria POLYSTICTA, Borr. E. Bot. Suppl. 2741. (1832.) 



Sussex 1 Mr, Borrer, Suffolk ? Bev, G. B. Leathes, 



The singular nature and appearance of the thallus dis- 

 tinguish this at first sight. It seems formed of an 

 extremely thin tartareous smooth and even layer, white, 

 yellow or green, which is cracked, as it were, by contrac- 

 tion, into minute, very angular, areolae or scales, exposing 

 in the interstices the thick black substratum immediately 

 underneath. 



