216 BRITISH DESMIDIACEJ1. 



Vertical view broadly elliptic, with, three granules at 

 the middle on each side and 2 just within, also with 

 two short, rather distant series (of 4 granules each) 

 extending inwards from each pole ; cell-wall punctate. 



Zygospore unknown. 



Length 38-40 //, ; breadth 28-35 /*,; breadth at base 

 of semicells about 25-28 /x; breadth of apex 24 /x ; 

 breadth of isthmus 10 ^; thickness 24 JJL. 



ENGLAND. Near Bowness, Westmoreland ! 



WALES.- -Capel Curig, Carnarvonshire ! 



Geogr. Distribution.- - Galicia in Austria (var.). 

 Australia (var.). New Zealand. 



Nordstedt regards tliis species as perhaps nearest to 

 C. monomazum Lund, and C. cristatum Ralfs (consult pp. 139 

 and 140) owing to the double series of marginal granules, 

 but the semicells are of rather different form and the granules 

 are absent from the flattened apex. 



193. Cosmarium quinarium Lund. 

 (PL LXXXV, figs. 9, 10.) 



Cosmarium quinarium Lurid. Desm. Suec. 1871, p. 28, t. 2, f. 14; Lagerh. 

 Bidr. Amerik. Desm.-fl. 1885, p. 236; Cooke, Brit. Desm. 1887, p. 114, 

 t. 40, f. 7 [figure bad] ; De Toni, Syll. Alg. 1889, p. 1014 ; W T est, Alg. 

 N. Wales, 1890, p. 290 ; Alg. W. Ireland, 1892, p. 158 ; Alg. Engl. Lake 

 Distr. 1892, p. 728; Roy & Biss. Scott. Desm. 1894, p. 173; Nordst. 

 Index Desm. 1896, p. 219; West & G. S. West, Alg. S. England, 1897, 

 p. 490; G. S. West, Alga-fl. Cambr. 1899, p. 218; West & G. S. West, 

 Alga-fl. Yorks. 1900, p. 76 ; Alg. N. Ireland, 1902, p. 39. 



Ursinella quinaria Kuntze, Revis. gen. plant. 1891, p. 925. 



Cells somewhat small, subhexagonal in general out- 

 line, about 1J times as long as broad, deeply con- 

 stricted, sinus narrowly linear with a slightly dilated 

 extremity ; semicells broadly pyramidate-truncate, 

 basal angles obtuse, apical angles rounded, sides 

 convex, apex truncate, margin furnished with 14-15 

 acute granules which give it an acutely undulate 

 character, with a series of 10 acute or rounded 

 granules just within the margin, and witli 5 large 

 granules in the centre disposed in two transverse 

 series, 3 in the upper series and 2 in the lower series, 

 with about 3 punctulations between them. Side view 



