Howe and Underwood: The Genus Riella 21G 



described and figured. References to the principal literature dcal- 

 in^"- with the genus, together with the names and distribution of 

 the species hitherto described, are given below : 



Riella Mont. Ann. Sci. Nat. III. i8 : i i. 1852. Leitgeb, Un- 

 tersuch. Leberm. 4 : 7A-^7- P^-7< S. f.iS. 1879. Trabut, 

 Rev. Gen. Bot. 3 : 449. 1891. Goebel, Flora, 77: 104- 

 108. pi. 2. f. /-?. 1893. Schiffn.; K. & W Nat. Pflanzcn- 

 fam. i': 51. 1893. Stephani, Bull. Herb. Boiss. 7: 

 658. 1899. 



Duriaca Bory & Mont. Compt. Rend. Hebd. Acad. Sci. 16 : 

 I I 15. 1843 ; Ann. Sci. Nat. HI. i : 228. 1844. G. L. & 

 N. Syn. Hep. 593. 1846. Not Diiricita Merat, Mem. 

 Soc. Roy. Sci. Lille, 1827-28 : 432. 1829. Not Z)//;7- 

 eua Boiss. & Reut. Diag. PI. Nov. Hisp. 14. 1842. 



Maisonnnivea Trevis.* Mem. R. 1st. Lomb. HI. 4: 442. 1877. 



Diiridla Clauson & Billot, /<^r Schiffn., /. r. 



Riella Battandieki Trab. Rev. Bryol. 13: ^5. pi. 3. 1886. 



Schiffn. Bot. Centralb. 27: 240. //. /./. 5. 1886. 

 Algeria: Maison-Blanche near Algiers, Battandkr, Trabut. 

 Exsicc: Husnot, Hep. Gall. no. 173. 

 Forma Gallica (Bal.) Corbiere, Rev. Bryol. 29: 113. 1902. 

 Riella Gallica Bal.; Trab. Rev. Gen. Bot. 3: 450. //. iS. f. 



G. 1891. 

 France: Roquehaute, near Beziers, Herault, Balansa, 1866, 



Crosals, 1902 ; mare de Rigaud near Agde, Herault, Croz- 



als, 1902. 



Riella Cossoniana Trab.; Batt. & Trab. Atlas Fl. Alg. i : 6. //. 

 2. f. 1-8. 1886; Rev. Bryol. 14: 12.//. 1887. 

 Algeria f: El Kreider, Province Oran, Cosson, 1854; Tra- 

 but, 1885. 

 Exsicc: Husnot, Hep. Gall. no. 174. 



*Trevisan rejected Riella Mont, on account of Riella Raf.; L6v.; Orb. Diet. 

 Univ. Hist. Nat. 8 : 488. 1849. This, however, is a nomen rtiidum and is probably 

 a misprint for Rimella Raf. Jour. Phys. 89 : 106. 18 19. 



t Allusions to the occurrence of Riella Cossoniana in the Canaries have recently ap-^ 

 peared in print (Bot. Tidsskrift, 24 : 327. 1902 ; Rev. Bryol. 29 : no. 1902), but 

 it is possible that these refer to Riella affinis, described below as new. 



