TRYPETHELIACEAE. 529 



2. TRYPETHELIUM Spreng. 



Spores four-celled. 



Spores over 35 u in length. 1. T. ochrothelium. 



Spores under 30 u, in length. 

 Stroma dark brown to black. 



Stroma little developed, the individual peri- 



thecia evident. 2. T. tropicum. 



Stroma well-developed, merely the tips of the 



perithecia showing. 3. T. mastoideum. 



Stroma some other color. 

 Thallus rusty-orange. 



Stroma flat and covered by the thallus. 4. T. aeneum. 

 Stroma elevated, conical. 5. T. ferrugineum. 



Thallus some other color. 



Stroma irregularly linear-elongated, peri- 

 thecia often showing a serial arrange- 

 ment. 6. T. catervarium. 

 Stroma rounded, oval, or oblong. 



Stroma elevated, the black tips of the 



perithecia conspicuous. 7. T. ochroleucum. 



Stroma depressed, the tips of the peri- 

 thecia inconspicuous. 8. T. pallescens. 



Spores six to many-celled. 9. T. eluteriae and varieties. 



Stroma yellow within. 



Thallus smooth, stroma neither yellow nor pow- 



dery externally. 

 Stroma varying in color from ashy to fulvous 



or chestnut-brown, strongly convex. 9a. forma tj/pica. ' 



Stroma dark-brown or blackening, flattened. 9&. var. truncatum. 

 Thallus smooth or powdery, stroma yellow or 



powdery or both. 

 Thallus smooth, stroma lemon-yellow and 



powdery. 9c. var. citrinum. 



Both thallus and stroma covered with a sul- 

 phury or aeruginous powder. 9d. var. subsulphureum. 

 Stroma becoming brown or black within. 9e. var. nigricans. 



1. Trypethelium ochrothelium Nyl. Act. Soc. Sci. Fenn. 7: 494. 1863. 



On bark, The Bight, Cat Island : Isle of Pines, Cuba ; Colombia. 



2. Trypethelium tropicum (Ach.) Muell. Arg. Bot. Jahrb. 6: 393. 1885. 



Verrucaria tropica Ach. Lich. "Univ. 278. 1810. 

 Pyrenula tropica Tuck. Genera Lich. 273. 1872. 



On bark of various species, Andros, New Providence, Cat Island, Long Island : 

 widely distributed in tropical and subtropical regions of both hemispheres. 



3. Trypethelium mastoideum Ach. Lich. Univ. 307. 1810. 



Sathelium mastoideum Ach. Meth. Lich. 111. 1803. 



Trypethelium scoria Nyl. Expos. Pyren. 74 . 1858. Not Fee Essai Crypt. 

 69. 1824. 



On bark. New Providence and Bleuthera : widely distributed in tropical and 

 subtropical regions of both hemispheres. 



4. Trypethelium aeneum (Eschw.) Zahlbr. in Engler and Prantl. Nat. Pflan- 



zenfam. I 1 *: 70. 1903. 



Verrucaria aenea Eschw. in Mart. Fl. Bras. 1: 133. 1833. 

 Trypethelium Kunzei Fee, Ann. Sci. Nat. 1 : 23 : 446, pi. 15, f. 3. 1831. 

 Trypethelium heterochroum Tuck. Genera Lich. 260. 1872. 



On bark, Andros, near Nicholl's Town ; Crooked Island, at Landrail Point ; Ack- 

 lin's Island, at Boathouse Cove : Florida ; Cuba ; Costa Rica ; Brazil. 



5. Trypethelium ferrugineum Muell. Arg. Bot. Jahrb. 6: 392. 1885. 



On bark, Andros, at Deep Creek : Cuba. 



