206 APPENDIX. 



closely allied exotic species, to the AgarcDbian genufl Cham- 

 pia, with which it nearly, but not quite accords. My only 



other alternative would have been to establish anew generic 

 group for it and its allies, and this I have not thought it 

 necessary to do. 



Within the last few years several species have been 

 added to the British list, but are not included in the pre- 

 sent publication. The most interesting of these are the 

 following: — Desmarestia Dresnaii, Lamour., if it be not 

 merely a broad variety of D. ligulata; Leathesia crispa, 

 Harv., a new species found in the Clyde, by Mr. Hennedy ; 

 Ectocarpus tessellatus,~Kayd.; Cruoria pellita, Fr. ; and 

 C. adhcerens, Cr., both found by Prof. Walker Arnott ; 

 Actinococcus Hennedyi, Harv., a new species found by Mr. 

 Hennedy in the Clyde ; — and, " last not least," Naccaria 

 hypnoides, Ag., found by Miss Turner at Jersey, and by 

 Mrs. Gulson at Exmouth. This list is sufficient to show 

 that our shores are by no means exhausted, and to encou- 

 rage young collectors to explore every nook and harbour of 

 our islands, where many interesting novelties may still await 

 their gaze. 



AY. H. H. 



Trin. Coll., Dublin, 

 1st July, 1857. 



