440 NEW OR CRITICAL BRITISH MARINE AZ,GrM. 



or less evident, clear, hyaline, gelatinous substance. These nema- 

 thecia, which are sometimes of considerable size, seem to contain 

 only tetraspores, which are formed from the apical cells of the 

 thallus-filaments. It is possible that after the discharge of the 

 spores, a fresh sporangium is formed within the old empty one. 

 Sporangia of all ages occur in the same nemathecium ; the young 

 undivided, and the empty sporangia somewhat resembling unicellular 

 paraphyses. The genus Porphyrodiscns forms a link between the 

 genera Hildenbrandtia and Hamatocelis ; from the former it is dis- 

 tinguished by the external nemathecia, and from the latter by the 

 absence of paraphyses, and the much more prominent nemathecia. 

 In Ha.matoceJis, indeed, the tetraspores may be said to be imbedded 

 in the superficial layer of the frond rather than in external nema- 

 thecia. They are, moreover, always accompanied by multicellular 

 filaments (paraphyses or unaltered thallus-filaments). 



I cannot close this note without referring to the lamented 

 death of my friend Mr. George William Traill, of Edinburgh, which 

 took place at his residence in Joppa, Midlothian, on Wednesday, the 

 7th of April of the present year. By his death a blank is left in 

 the ranks of British algologists which it will be hard to fill. Really 

 good collectors are now so scarce that we can ill afford to lose such 

 an accurate and painstaking observer as Mr. Traill. For more 

 than twenty years much of his spare time was devoted to collecting 

 and classifying the British marine algfe, more especially those of 

 Orkney, his native place, and of the Firth of Forth, on the shores 

 of which he had so long resided. Always ready to assist other 

 workers in the same field, much of Mr. Traill's collecting was 

 undertaken to supply the wants of algologists living at a distance 

 from the sea, and but a small proportion of the specimens he 

 gathered are now contained in his herbarium. Never strong for 

 years before his death, he had to contend with chronic ill-health, 

 and it is marvellous how he managed to do so much and such 

 useful work. The following is a list of the published papers on 

 algological subjects written by Mr. Traill : — 



1. An Alphabetical List of the Parasitic Algfe of the Firth of 

 Forth {Froc. Royal Dublin Soc. 1882). 



2. The Marine Algae of Joppa {Trans. Bot. Soc. Ed. 1886). 



3. A Monograph of the Algfe of the Firth of Forth. 1885. 



4. The Marine Algae of Elie {Trans. Bot. Soc. Ed. 1888). 



5. The Marine Algte of the Orkney Islands {I.e. 1890). 



6. Notes on New and Eare Algae {l. c. 1888). 



7. The Marine Algte of the Dunbar Coast {l. c. 1890). 



8. On the Fructification of Sphacelaria radicans {I. c. 1888). 



9. Supplementary Notes on the Marine Algae of the Orkney 

 Islands {I. c. 1892). 



10. Supplementary Notes on the Marine Algae of the Orkney 

 Islands : (2) Island of N. Eonaldsay (L c. 1896). 



Most of these papers were illustrated with herbarium specimens 

 of the rarer species. 



