SOME NEW BRITISH DISCOM YCETES. 
115 
No. 384; Leveille in Moug. Stirp. Crypt., fasc. xv. (1860), No. 
1479. 
On Betula alba. Oxford ! (Mr. Baxter.) 
The transverse cracks in the bark expose the linear series 
(|-1 in. long), composed of the three forms, the ascigerous cups 
being rarest. Tulasne gives the sporidia as 35-45 X 3-4 /x, ; but 
in the Oxford specimen they are as given above. He says that 
.long before the fruit can appear the linear series changes the 
natural colour of the white parchment-like bark to brown, and that 
underneath each sorus is a black linear ovate zone in the wood. 
ALGaE BRITANNICA RARIORES EXSICCATAE. 
Fasciculus III. 
By E. M. Holmes. 
51. Anabaina variabilis, Kiitz. 
Harwich, June, 1885, E. Batters. 
52. Bangia ceramicola, Chauv. 
Weymouth, October, 1884, E. M. Holmes. 
53. Callithamnion fruticulosurn, J. Ag ., on Chondrus crispus. 
Swanage, June, 1885, E. M. Holmes. 
54. Callithamnion tenuissimum, Kutz. 
Falmouth, June, 1884, E. M. Holmes. 
55. Cladophora expansa, Kutz , on Zostera leaves. 
Weymouth, September, 1884, E. M. Holmes. 
56. Cladophora flexuosa, E. B. 
Cley, Norfolk, August, 1886, E. Battel's. 
57. Cladophora hirta, Kiitz. 
Cley, Norfolk, August, 1886, E. Batters. 
58. Cladophora refracta, Roth. 
Weymouth, November, 1883, E. M. Holmes. 
59. Clathrocystis roseo-persicina, Cohn. 
Harwich, June, 1885, E. Batters. 
60. Codiolum gregarium, A. Braun. 
Lynmouth, August, 1883, E. M. Holmes. 
61. Dasya venusta, Harv. 
Studland, near Swanage, October, 1886, E. M. Holmes. 
62. Ectocarpus CEespitulus, J. Ag. 
Newquay, June, 1884, E. M. Holmes. 
63. Ectocarpus irregularis, Kiitz. 
Bognor, May, 1885, E. M. Holmes. 
