io The Irish Naturalist. 



a gravel-pit near Clontarf, and which included Bunias orientalis, 

 Sisymbrium locsclii, Silene qrmeria, Anacyclus tadiatus ; and the 



curious grass Lolium rcpcns, f. cristatum, gathered near Glas- 



nevin. 



Some other plants appear to have secured a firm hold in the 

 immediate vicinity of Dublin, but have not, yet at least, ven- 

 tured further afield. Note the abundance of Mercurialis annua, 

 which chokes the city back-gardens and rubbish-heaps, yet 

 vanishes as soon as we get clear of the houses and smoke of 

 the town. The Mercury, however, has established itself in one 

 or two spots in the South of Ireland, and a better illustration 

 is furnished by the rare Sisymbrium irio, which grows abund- 

 antly in the Dublin suburbs, and is unknown elsewhere in 

 Ireland. One or two other plants, on the contrary, which are 

 quite recent arrivals in Ireland, have been rapidly spreading 

 since they took up their abode with us. Two excellent 

 examples are furnished by Diplotaxis muralis and Li?iaria 

 minor, both of which, it is to be remarked, select railway 

 tracks as their favourite abode. 



Diplotaxis was first found at Portmarnock in 1837, and 

 rapidly increasing, is reported as abundant at Portmarnock 

 and Baldoyle in " Cybele Hibernica" (1866). More recently 

 it is recorded from Howth 1 and Sutton 2 ; and last season I 

 found it abundant on the railway from Amiens-street to 

 Howth Junction, a distance of five miles, and recorded its 

 spread to Skerries and away down into County Armagh. 3 

 Linaria ??ii?ior has a similar history. Mackay, in " Flora 

 Hibernica," remarks that he has not seen an Irish specimen, 

 but that the plant is reported to grow in County Cork. In 

 " Cybele " is published its first County Dublin station — 

 Stillorgan ; the "Guide to County Dublin" adds Sydney 

 Parade and the M.G.W. Railway ; Mr. Hart adds Howth ; and 

 last season Mr. Colgan noticed it on the railway from Clontra 

 to Bray River, and the writer found it along the same line the 

 whole way from Harcourt-street to Bray, and also at Wicklow 

 and Rathnew. 



The additions to the flora of County Dublin, and additional 

 stations for rarer species published in Mr. Colgan's paper, give 

 ample proof of the zeal with which the author is exploring the 



1 " Guide to County Dublin," 1878. 2 " Flora of Howth," 1887. 



> I.N., 1893. 



