202 THE JOURNAL OF BOTANY 



■''-Enteridium olivaccum Ehrenb. var. liceoides Lister. On a 

 chip of pine wood, Wringclitf. The clustered spores separate 

 this variety from Licca flexiiosa wliich it greatly resembles in form. 



Betimlaria lycoi:)erdon Bull. Common on logs and gateposts. 



Lycogala ejndendrum Fries. Very plentiful on rotten wood. 

 The young oethalia are coral-red and very conspicuous. 



Trichia j^ersimilis Karst. Lee Woods, Woody Bay, Ladywell. 



T. varia Pers. West Lyn valley. 



T. decipie7is Macbr. Everywhere very abundant. 



T. hotrytis Pers. Lee Woods and Woody Bay. 



Arcyria denudata Sheldon. Lee Woods and Ladywell. A very 

 handsome crimson species, common everywhere in Britain. 



*^. cinerea Pers. Common in all woods. 



■''A. po7niformis Post. Woody Bay Woods. 



A. incamata Pers. Everywhere abundant in July, scarcer in 

 August. Very beautiful when mature. 



''■A. nutans Grev. Lee Woods, W. Lyn valley. Tlie long 

 yellow sporangia resemble miniature loofah sponges. 



A STUDY OE BAEBAEEA VULGAEIS E. Br. 

 By a. Bruce Jackson. 



For several years I have made a critical study of the British 

 species of Barbarea. Eecently in this connection I have given 

 special attention to the variations of B. vulgaris E. Br., and I 

 propose to present some observations on this, the most widely 

 distributed species in our islands. As the result of comparing 

 carefully numerous living and dried specimens from all parts of 

 Europe, including a very large number of examples from widely 

 separated localities in Britain, I have found it necessary to revise 

 the generally accepted opinion as to the relationship of B. vulgaris 

 and B. arcuata — plants which, as I shall presently show% have 

 been much misunderstood. 



Our plant was described by Linnaeus (Sp. PL, 660 (1753) excl. 

 vars.) as Erysimum Barbarea, and subsequently by Eobert Brown" 

 (in Alton, Hort. Kew. ed. 2, iv, 109 (1812)) who described it as 

 ''Barbarea vulgaris foliis inferioribus lyratis : lobo terminali 

 rotundato; superioribus obovatis dentatis." 



Seven years later, the plant afterwards known to botanists as 

 B. arcuata Eeichb. was described as a species by Opiz under the 

 name of Erysimum arcuatum in J. & 0. Presl, El. Cech. 138 (1819), 

 with the description " fol. inferioribus lyratis, superioribus 

 pinnatifidis, lobis terminalibus rotundatis, siliquis arcuato-falcatis 

 yequalibus. . . . Flores majores prascedente." 



Eeichenbach in his diagnosis of B. arcuata (in Flora, v. 296, 

 1822) says he was much impressed by finding this beautiful plant 

 in several fields at Dresden, and that he also came across it more 



* On the question of Eobert Brown's authorship of the Grucifercc in Alton's 

 Hort}is Kcwensis see Journ. Bot. 1912, Suppl. iii, p. 7. 



