369 
NEW OR CRITICAL BRITISH MARINE ALG. 
By E. A. L. Barrers, B.A., LL.B., F.L.8.* 
(Prate 414.) 
ERAL species, not previously noticed on the shores of the 
British Isles, have _Tecen tly been added to our marine alga-flora. 
@ expe 
country whose shores have been industriously and successfully ex- 
plored for the best part of a century in the an for marine alge. 
n the present paper I pro ee to give a list, with descriptions of 
some undescribed forms, of the more eee rea species that have 
recently come under my notice. 
MyxopnYces. 
OBYRSA MARINA Rabenh. Flor. eur. Alg. ii. p. 68 Ce 5). 
3. PLEcTONEMA . ae Gomont, Bulletin i la Soc. bot. de 
France, vol. xlvi. p. 84, Feb. 1899. Mixed with Calothrix cag 
lorum and other Mee oheese on dee near high-water mar 
Clacton, Feb. 1893, and Sin e, Aug. 1894; F. A. B. 
4. P. Barrersi Gom. l.c. p. 36. Mixed with Prasiola stipitata, 
a on rocks near high- ee raark. Berwick-on-T weed, Feb. 1887; 
E. A, B, 
5. Puormiprum Ecrocarri — l.c. p. 87, pl. 1, fig. 13. 
P. persicinum Batt. (non Gom.) arte. This — forms 
a pink film over Ectocarpi or on co surface of the mud at high- 
water mark. Cumbrae, Aug. 1891; H. 4. B. Plymouth, Tune, 
‘ebner. 
6. Scuizornrix vacinata Gom. Monographie des Oscillariées, 
p. 40; pl. vii. a 1-4. Near the Picket Heats Sidmouth, Aug. 
1885; E. A. Cumbrae, Aug. 1899; Mrs. Robertson. I am 
indebted to a Gomont for the aout hentiast of this and the 
three preceding species. 
7. Nostoc ENTopHytum Bornet & Flahault, Rev. des Nostocacées 
heterocystées in phonies d. Se. Nat. 7e ser. Bot. vii. p To 
this species I refer some specimens of a microscopic Nostoe which 
I found embedded in the thallus of Rivularia Biasolettiana at Cumbrae 
* See Journ. Bot. 1895, 274-6; 1896, 6-11, 384-390; 1897, 433-440. 
JournaL or Borany.—Vou. 88. [Ocr. 1900.] 
