550 CALOPLACACEAE. 



2. USNEA Adans. 



1. Usnea florida (L.) Web. var. strigdsa Ach. Meth. Lieh. 310. 1803. 

 On trees, Crooked Island, at Stopper Island : cosmopolitan. 



Family 15. CALOPLACACEAE. 



Thalline exciple never present. 1. Blastenia. 



Thalline exciple present, or sometimes disappearing in old apothecia. 2. Caloplaca. 



1. BLASTENIA Mass. 



Disk of apothecia orange or rusty. 1. B. ferruginea. 



Disk of apothecia dark brown to black. 2. B. floridana. 



1. Blastenia ferruginea (Huds.) Koerb. Syst. Lich. Germ. 184. 1855. 



Lichen ferrugineus Huds. Fl. Ang. 444. 1762. 

 On bark, New Providence : cosmopolitan. 



2. Blastenia floridana (Tuck.) Zahlbr. in Engler & Prantl, Nat. Pflanzenfam. 



I 1 *: 227. 1907. 



Lecanora floridana Tuck. Proe. Am. Acad. 5: 402. 1862. 

 Placodium floridanum Tuck. Syn. N. A. Lieh. 1: 179. 1882. 



On bark, New Providence : widely distributed in tropical America. 



2. CALOPLACA Th. Fr. 



Thallus conspicuously white-powdery. 1. C. galactophylla. 



Thallus not at all white-powdery. 



Thallus on bark, copiously isidiose. 2a. C. aurantiaca var. isidiosella. 



Thallus on rocks, without isidia. 



Apothecia superficial on convex, thick, thal- 

 line areoles. 2b. C. aurantiaca var. erythrella. 

 Apothecia immersed in flat, thin, thalline 



areoles. 2c. C. aurantiaca var. diffracta. 



1. Caloplaca galactophylla (Tuck.) Kiddle. 



Placodium galactophyllum Tuck. Proc. Amer. Acad. 12: 171. 1877. 

 On limestone, New Providence : Kansas. 



2. Caloplaca aurantiaca (Lightf.) Th. Fr. Lich. Arct. 116. 1860. 



Lichen aurantiacus Lightf. Fl. Scot. 2: 810. 1777. 



2a. Caloplaca aurantiaca var. isidiosella (Crombie) Piddle. 



Lecanora aurantiaca var. isidiosella Crombie, Journ. Linn. Soc. 15: 437. 



1877. 

 Lepraria Bassiae Ach. Meth. Lich. 5. 1803. 

 Placodium aurantiacum subsp. Bassiae Wainio, Journ. Bot. 34: 67. 1896. 



On bark, New Providence : Jamaica ; St. Thomas ; St. Vincent ; Guadeloupe ; 

 India. 



2b. Caloplaca aurantiaca var. erythrella (Ach.) Th. Fr. Lich. Scand. 178. 1871. 

 Lichen erythrellus Ach. Lich. Prodr. Suee. 43. 1798. 

 On limestone, Eleuthera Island : probably cosmopolitan. 



