1914-15.] BOTANICAL SOCIETY OF EDINBURGH 423 



whorls are farther apart, and the stem is not red where 

 they branch off, as in Elodea." 



It has been variously named as under : — 



Hydrilla veHicittata, Caspary, in Bot. Zeit., xiv, 899 

 (1856). 



H. ovalifolia, Rich., Mem. Inst. Paris, ii, 76, t. 2 (1814). 



H. dentata, Casp., Bot. Zeit., xi, 805 (1853). 



JJdora verticiUata, Gorski in Eichwald. Skizze v. Lithuan, 

 etc., 127 (1830). 



U. lithuanicus, Besser, in Flora, ii, Beibl. 12 (1832). 



JJ. occidental™, Koch, Syn. PL Germ., ed. i, 669 (1837). 



U. pomera/nica, Reichb., Icones, £. 104 (1845). 

 ? Serpicula verticiUata, L.f. supp. plant., 416 (1781). 



Asch. unci Graeb., Syn. Milleleup. FL, i, 399 (1897). 



In Europe it occurs near Stettin in Pomerania, S.E. 

 Prussia; Russia — in Wilna, Finland, and Witsbk govern- 

 ments ; in Asia, Central Africa. Madagascar, Mauritius, 

 and Australia. 



How far the species is really indigenous to Europe is 

 doubtful. Mr. Pearsall considers that the richness of the 

 " Water " in aquatic vegetation is the result of the large 

 number of aquatic birds that occur there : " wild ducks, 

 coots, water-hens, etc., by the score." But it seems hardly 

 possible that seeds could be conveyed from such far distant 

 places : perhaps on the mud of the feet ?, but I doubt in 

 the crops, as Danish naturalists have determined that birds 

 on migration as a ride fly with empty stomachs, and 

 several that a friend of mine dissected in the spring 

 mi oration to Enoland had done the same. 



Additional Mosses from Duncraig. West Ross-shire. 

 By James Stirton, M.D., etc. 



(Read Sth April 1915.) 



For several years I have been considerably exercised in 

 the study of a peculiar, almost unique, group of mosses the 

 area of whose growth and spread is rather restricted. This 

 area forms a narrow belt from north to south, extending 

 from the Island of Lewis to the south of Ireland and from 

 the west coast of Scotland to the Outer Hebrides. In the 



