NOTES OM ASCOPIirLLUM MACKAII, F. ROBERTSONI. 271 



As I had gathered Ascophyllmn Mackaii in Birter- 

 buie Bay, Ireland, a few years ago, the Lochranza 

 plant seemed to be the same or closely allied to it. 

 I submitted specimens to Mr. E. A. L. Batters, LL.B., 

 F.L.S., one of our ablest phycologists, who pronounced 

 the plant to be A. Mackaii; but as it difPers in 

 various particulars from the type, he proposes to 

 give it the above varietal name* 



Harvey figures Fucus Mackaii in his Phycolocjia 

 Britannica, vol. i., pi. Hi., and states that a doubt 

 rested on the validity of the species, "the resemblance 

 in many respects to a dwarfed variety of Fucus 

 nodosus suggesting the probability that it is only a 

 form of that plant." In one particular the suggestion 

 is so far supported by the Lochranza plants as they 

 are greatly infested by Polysijihonia fastiyiata, a 

 constant parasite of Ascophyllum nodosum. 



A. Mackaii has also been recorded from Loch Sea- 

 forth, Arisaig, Loch Coul, Sutherland, East of Skye, 

 and head of Loch Duich. 



* See Grcrilha, vol. xxL (1892), p. 13. 



