276 PTSENOCARPEI [vERBfCAKIA 



The order is disidnguished by the cnistaceous thallus, bright-green 

 gonidia and simple fruits. There are seven British genera : — 



Gonidia not present in hymenixim. 

 Paraph^es disappearing. 



Spores simple 105. ■Verruearia. 



Spores 1-3-septate 106. Theliditun. 



Spores mnriform 107. Polyblastia. 



Paraphyses persistent. 



Spores simple 108. Thrombinm. 



Spores multi-septate 109. Qongylia. 



Spores muriform 110. Microglsena. 



Gonidia present in hymenium. 



Spores mnriform 111. StavLrothele. 



105. VEREUCARIA Pers. in Ust. Ann. Bot. vii. p. 23 (1794) 

 pro parte (non Web. nee Humb.), emend. Th. Fr. Lich. Arct. 

 p. 267 {I860).— Lithocia S. F. Gray Xat. Arr. i. p. 497 (1821) 

 pro parte. (PI. 41.) 



Thallus crustaceous, continuous, areolate or pulverulent, some- 

 times developed within the substratum. Algal ceUs Pleurococeus 

 or PalmeUa. Perithecia immersed in the thallus or superficial, 

 the outer wall of a carbonaceous or horny structure completely 

 surrounding the perithecium {entire) or developed onlv over the 

 upper part (dimidiate), opening above by a pore or slit (ostioh) ; 

 paraphyses soon becoming mucilaginous and disappearing ; 

 filaments within the ostiole (perijphyses) well developed ; asci 

 8-spored ; spores eUipsoid or subglobose, colourless, rarely brown. 



The Verru<:aina of early authors was based on characters that 

 belong to widely different lichens. Persoon first defined the genus as 

 possessing subglobose fruits ; Th. Fries restricted it to those species 

 with simple usually colourless spores and with paraphyses more or 

 less dissolved in mucUage. In some species the dark outer peritheeial 

 wall is strongly developed only over the upper half of the fruits and 

 spreads out at the base, a colourless or brownish layer of cells called 

 the inner wall or tunic being continued under the base ; this character 

 is considered by some lichenologists to have generic value — Litliocia 

 S. F. Gray, Lithoicea Massal. Mem. Lich. p. 141 (1853). 



Maritime species growing within reach of waves or spray from the 

 sea ; thallus more or less gelatinous when moist. 



1. V. maura Wahlenb. in Ach. Meth. Suppl. p. 19 (1803).— 

 Thallus black or dark-reddish or brownish-black, thickish, or 

 thin, smooth or subgelatinous, shining or occasionally somewhat 

 scabrid, cracked into minute areolie. Perithecia moderate in 

 size, hemispherical, scattered, immersed in the thallus, the ostiole 

 more or less visible ; peritheeial wall dimidiate and spreading at 

 the base, a thin black layer being continued under the base ; 

 spores ellipsoid, 0,012—17 mm. long, 0,007-8 mm. thick, some- 

 times i-ather larger ; hymenial gelatine wine-red with iodine. — 

 Hook. Fl. Scot, ii p. 43 & in Sm. Engl, Fl. v. p. 154; Grev. Fl. 



