I902. BuKBiDGK & Coi^GAN. — A New Senecio Hybrid. 317 



between the two species, while the fertilizing effect is quite 

 one-sided. The parentage of the hybrid, then, should be thus 

 expressed: — $ S. cineraria DC, x ? S.Jacobcea L- 



The appearance of 5". albescens in Ireland affords a most in- 

 teresting example of the disturbing influence which may be 

 exercised b}^ the introduction of a new element into a flora 

 already in a state of equilibrium. The alien Senecio Cineraria 

 from the shores of the Old World sea has not merely succeeded 

 in founding a vigorous colony a thousand miles northward of 

 the Pillars of Hercules, — it has contracted an alliance there 

 with a native species equally vigorous and aggressive, and the 

 fruit of this union has been a new race in which the characters 

 of both parents are happily blended. Whether this new race 

 will show^ itself capable of self-perpetuation 3^et remains to be 

 seen. The fact that it produces, though in small quantity, 

 freely germinating seeds, would suggest that it may have this 

 power of self-perpetuation ; and, should this prove so, then a 

 new species or sub-species of hybrid origin maj^ be said to 

 have been born on the shores of Killiney Bay. 



This is the second instance of an alien Senecio from Southern 

 Europe having hj^bridized naturally with a native species in 

 Ireland. The first instance, as is well known to Irish botanists, 

 is to be found in the plant detected by Isaac Carroll near 

 Cork in 1853, named b}^ Syme as a variety of the Common 

 Groundsel, but subsequently set down by Dr. Focke as a 

 natural crossing of that species with S. sqnalidus Linn. 



Dublin. 



KxpivAXATiox OF Pirate 5. 



Fig. I.— Senecio facobcea L. From a specimen gathered at Portmarnock, 



Co. DubHn, July 14, 1902. 

 F'ig. 2. — Seiucio Cineraria DC. From a specimen gathered on Sorrento 



Cliffs, Dalkey, Co. Dublin, July 24, 1902. 

 Fig. 3. — X Senecio albescens — A hybrid between .S". Cineraria and S.Jacobcea. 



ajDproaching more closely to the latter. I'rom a specimen 



gathered on the sea banks at Vico, Dalkey, Co. Dublin, 



July 24, 1902. 

 Fig. 4 — A hybrid of like parentage with S. albescens, but more closely 



approaching to S. Cineraria. Perhaps identical with S. 



ca/vescens (Jslor. & De Not., Florida Caprarice, 1839.) From a 



specimen gathered at Vico, July 24, 1902. 

 All of the figures about 1/3 natural size and photographed from her- 

 barium specimens in which the form of the flowers is imperfectly shown. 



