294 E. A. Vainio, Lecideales. 



Rh. umbilicatum (Ram.) Jatta 



Fl. It. Crypt. Lich. (1911) p. 689, incl. Rh. calcareum Jatta 1. c. 

 Lecidea umbilicata Ram. Mem. Soc. Linn. Paris 1827 p. 434, sec. spe- 

 cim. a Nyl. determ. ; Des Moul. Act. Ac. Sc. Bord. 1844 p. 105; Nyl. in 

 Gasil. Contr. Lich. Plat. Centr. (1898) p. 58. L. petraea 2. umbilicata 

 Nyl. Prodr. Licli. Gall. (1857) p. 374. L. calcaria a. Weisii Schaer. Lich. 

 Helv. Exs. VII et VIII (1828) n. 184 p. p. (sec. Arn. Lich. Exs. 215 d), 

 En. Lich. Eur. (1850) p. 121. Diplotomma Weissii Mass. Ric. Lich. Crost. 

 (1852) p. 99, Sched. Grit. (1855) p. 32. D. Weisii Krempelh. Lich. Bay. 

 (1861) p. 209. Siegertia Weisii Arn. Lich. Tirol XX (1879) p. 14. Rh. 

 calcareum a. Weisii Th. Fr. Lich. Scand. II (1874) p. 631. Diplotomma 

 calcareum Krempelh. Fl. 1853 p. 220 (non Lichen calcarius L., nee Weis 

 sec. Arn. I.e.). Forsan L. amylaceus Ach. Vet. Ak. Handl. 1794 p. 191 

 (conf. Th. Fr. 1. c. p. 536). L. rimosas Dicks. Fasc. Crypt. Brit. (1785) 

 p. 12 sec. Leight. Lich. Great Brit. 3 ed. (1879) p. 379 (conf. autem 

 Schaer. Lich. Helv. Spic. p. 144), haud Retz. (1779). 



Exs. Fr. Lich. Suec. Exs. XIV (1833) n. 412 (in herb. Nyl.). — 

 Hepp Flecht. Eur. I (1853) n. 147 (sec. Stizenb.). — Arn. Lich. Exs. 

 (1869) n. 215 b, (1883) d (a et c non vidi). — Lojka Lich. Regn. Hung. 

 Exs. IV (1884) n. 194. 



Thallus crustaceus, crassus aut modice incrassatus, continuus 

 aut rimosus vel areolato-diffractus, uniformis aut saepe demum am- 

 bitu subeffiguratus, sat laevigatus, albus, cretaceo-opacus, nee KHO, 

 nee jodo reagens, hypothallo indistincto aut linea obscurata indicate. 

 Apothecia primum margine instructa thallino, vulgo crasso, extus 

 cinerascenti-obscurato subpruinosoque, intus albido, demum toto ob- 

 scurato tenuioreque, disco piano, nigro, nudo, haud papillato. Epithe- 

 cium olivaceum. Sporae 8:nae, decoloratae aut demum obscuratae, long, 

 circ. 0.021 — 0.030, crass. O.012 — O.015 mm, murali-divisae, cellulis haud aut 

 rarius sat numerosis. 



Distr. Praesertim ad rupes calcarias etiam in Scandinavia pro- 

 veniens, in Fennia nondum collectum est. 



Facie externa saepe vix satis a Rh. concentrico v. excentrico 

 differt, apotheciis novellis parathecio obscurato nullo instructis eo 

 dissimile. Crystalla calcii oxalat. nulla in thallo observavi. Apothecia 

 crebra aut saepe irregulariter aggregata, disco circ. O.5 — 1.3 mm lato, 

 saepe difformi, margine thallino gonidiis mox emorientibus, saepe 

 KHO lutescente, ex hyphis thallinis, crebre irregulariter contextis, 

 partim subconglutinatis formate, demum toto aeruginoso- aut olivaceo- 

 fuligineo. Hypothecium rubricoso-fuligineum. Hymenium O.no — O.iso 

 mm crassum, jodo persistenter caerulescens. Paraphyses parce ra- 

 moso-connexae, crebre septatae, gelatinam sat abundantem percurren- 

 tes. Sporae septis transversis 3—4, loculis septis longitudinalibus 

 1 — 2 divisis, strato gelatinoso sat crasso indutae. 



