336 



LICIIKXACET. 



[PAXXAHIA. 



Owing to the separation of the following genus formerly included in it, 

 this is now much better limited both in the character of the thallus and 

 of the apothecia. Most of the species are exotic ; but, with a few ex- 

 ceptions, those which are European occur in this country. 



Fig. 55. 



Pannaria rvbiginosa Del. a. Vertical seclion of thallus with hypothalline 

 filaments, X 200. b. A theca and paraph y sea, X 350. c. Spores, xf>00. d. 

 Jointed steriginata and spermatio, x500. 



1. P. rubiginosa Del. in Dub. Bot. Gall. (1803) p. 006. Thallus 

 orbicular, membranaceous, appressed, smooth, laciniate at the cir- 

 cumference, livid-glaucous or pale ; laciuiae somewhat plane, inciso- 

 lobulate and crenate, crenulate and silvery- white at the margins ; 

 hypothallus spongioso-tomentose, bluish-black. Apothecia mode- 

 rate, plane, red or reddish-brown, the thalline margin crenulate, 

 silvery- white ; spores ellipsoid, often somewhat acuminate at the 

 apices, 0,017-30 mm. long, 0,006-0,011 mm. thick; hymenial 

 gelatine bluish with iodine. Mudd, Man. p. 122 ; Cromb. Lich. 

 Brit. p. 42 ; Leight. Lich. Fl. p. 164, ed. 3, p. 150. Parmelia ru- 

 biginosa Gray, Nat. Arr. i. p. 440 ; Hook. Fl. Scot. ii. p. 53. Par- 

 melia jilumbea ft. affiuis Tayl. in Mack. Fl. Hib. ii. p. 142. Lichen 

 rubiginosus Thunb. Fl. Cap. (1794) p. 176. tiquamaria affinis Sm. 

 Eng. Fl. v. p. 196. Lichen affinis Dicks. Crypt, fasc. iv. p. 24, t. 12. 

 f. 6 ; Eng. Bot. t. 983. 5rt*. Exs. : Leight. n. 234 ; Cromb. n. 53 ; 

 Larb. Lich. Hb. n. 11. 



A rather beautiful plant, well marked by the silvery-white margins of 

 the laciuifle and by the bluish-black hypothallus. In the centre the 



