230 DUBLIN UNIVERSITY 



and Anachris ahinasfrum. Here again the centres of distribution favour 

 the hypothesis of the former having extended to the south-west of Ire- 

 land, where it occurs abundantly in several parts of the county of Cork, 

 and as far to the eastward as Clonmel, and westward as Corofin, in the 

 county of Clare, near to where it is met by other outlying types of the 

 North American Flora, viz., Eriocaulon septangulare, Naias flexilis, &c. 



The Anachris is certainly a plant of very recent introduction to 

 these islands, through which it has spread to a greater extent and 

 with more rapidity than any other colonist plant has done, with 

 which I am acquainted, not even excepting Veronica Buxbaumi. I ob- 

 served it in Ireland during the same year it was first noticed in England 

 and Scotland ; and though I then obtained only a small portion of it 

 from a pond in the garden of the late I. M. D'Olier, Esq., of Booters- 

 town, which I brought to Glasnevin, it now abounds in the River Tolka 

 from the Botanic Garden to the sea, and in the Royal Canal for miles, 

 both up and down, from this known centre of distribution, as well as 

 through other parts of the country. 



In the list of seventy-three European species supposed to be natu- 

 ralized in Britain, Mercurialis annua and Geranium pyreniacum are 

 placed, both of which I consider truly wild in this country. The Mer- 

 curialis is well known to be one of the common weeds through the 

 county of Dublin, but it is very local in Ireland. Geranium pyreniacum 

 I have collected specimens of in the following counties : — Dublin on 

 the east, Antrim on the north, Mayo in the west, and "Waterford in the 

 south. 



Such plants as Myrrhis odorata, Saponaria officinalis, Sylibum 

 marianus, Cheiranthus cheiri, Antirrhinum majus, Anchusa sempervi- 

 rem, Sedum dasyphyllum, Sedum album, and Veronica Buxbaumi, 

 are all met with plentifully in some parts of the country, but the habi- 

 tats are generally in such suspicious places as will hardly warrant their 

 being considered truly indigenous. The Silybum, Virgin Mary's 

 Thistle, as it is called, is supposed to have been brought from the East 

 to Britain by the Crusaders, whence it has probably also come to Ireland. 



The introduction to Britain of eighty-three species enumerated by 

 M. de Candolle is not considered by him to have been owing in a great 

 degree to what are usually termed natural causes, such as currents of 

 the sea, prevailing winds, the agency of birds and beasts, but rather by 

 man alone, not accidentally by the seeds adhering to clothes, or trans- 



