Clare Island Survey — Phanerogamia. 10 45 



The great bulk of the flora of the island consists of individuals which 

 must be classed as N N * — that is, they belong to species which are in sensu 

 strieto native somewhere on the island ; but they (the individuals in question) 

 occupy disturbed ground ; they represent the invasion of the farmland by 

 the indigenous flora ; and in less altered areas, such as the heath-land, they 

 represent the natural regeneration of the indigenous flora. 



Native species brought by artificial means into a native habitat (N * N) 

 or into an artificial habitat (N * *) form no recognizable part, I think, of the 

 flora of the island ; though no doubt the sheep and cattle enlarge the range 

 of some of the native species by dispersing seeds, &c. 



A few plants which I believe to be native on the island, though their 

 claim is not altogether clear, may be referred to here : — 



Ulex europaeus. — Has its headquarters on rough stony ground at the east 

 end of the island, whence, I believe, it has spread to dry banks on which it 

 has the appearance of having been planted. 



Senecio Jacobaea. — Except in very dry places is replaced by S. aquaticus. 

 Many of the dry places in which it grows are artificial ; but it is found on 

 isolated sea-stacks near Doontraneen, and its absence from some suitable 

 dry spots on the island is probably due to the sheep. 



Arctium Nexdbouldii. — Native probably on the sands near the harbour, 

 which are its headquarters on the island. But in the case of a plant so 

 prone to ectozoic dispersal, certainty is impossible. 



Bidens tripartita. — Grows mainly in a roadside ditch near the chapel — an 

 artificial habitat ; but also in two places in wet ground on old grass-land, 

 where I think it is native. A few plants which appeared on the gravelly 

 beach inside the harbour in 1910 were probably brought from one of these 

 stations by means of the barbed seeds, which are so admirably adapted for 

 promoting dispersal by animals. But that one must be slow about assuming 

 such dispersal is shown by the following fact : B. cernua grows in great 

 abundance along the edges of the road leading from Louisburgh to Boonah, 

 along which much Clare Island traffic passes, and in autumn its barbed seeds 

 are ready in thousands for casual transport by man or animals. Yet it has 

 not succeeded in reaching the island. Did B. cernua instead of B. tripartita 

 (which is absent from the road-sides referred to) occur on Clare Island, one 

 would certainly have been tempted to ascribe, probably erroneously, its arrival 

 to the traffic by this route. 



Lemna minor. — Occurs only in one ditch near the chapel. Probably 

 brought by natural means (? birds) into this artificial habitat. It occurs also 

 in a pool on Caher Island, long uninhabited. 



