SciiAHFF — Former Land-Bridge between N. Europe and N. America. 13 



of the ten species alluded to are apparently of American origin. One, 

 however, the common European Ling {Ca/luna vulgaris), certainly has its home 

 in Europe. It is restricted in North America to a few localities on the coast 

 of Newfoundland and southward. . I sliall allude later on to some animals 

 with a similar range. A few of the other plants have rather a confined 

 distribution in Europe. Some, like the Water Lohelia {Lobelia Dortmanna), 

 are widely disseminated over the western parts of our continent.' 



Fig. 2. — JEriocaiiloii septangnlarc, growing in its native habitat in tlie West of Ireland. 



A'. Welch, Photo. 



A small group of plants is of particular interest to Irish botanists, as 

 being almost exclusively confined to the "West of Ireland and North America. 

 According to Messrs. Colgan and Scully, five species of plants occurring in 

 Ireland belong to this group, viz., Spiranthes Bomanzoviana, Sisyrmchium 

 angustifoliv.m, Eriocanlon septnngnlare, Naias flexilis, and ■Tunms tenuis. Two 

 of these, the Sisijrinchiiim and Juncus, may possibly have been introduced. 

 But Messrs. Colgan and Scully express the opinion that no doubt has ever 

 been raised as to the indigenous standing of the remaining three.^ All of these 

 plants are discontinuously distributed. An interval of more than 200 miles 

 separates the northern and southern stations in Ireland of the rare orchid 

 Spiranthcs Eomanzoviamc. The water plants Eriocaulon scptangidarc (fig. 2) 



'Eiigler, A., '' Entwicklungsgescliichte d. Floiengebiete," i., p. 15. 

 • Colgan, N., and K. W. Scully, " Cybele Hibernica," 2nd ed., p. 71. 



