COSMAEIUM. 135 



Lake Distr. 1892, p. 728; Schmidle, Beitr. Algenfl. Schwarzwald. tu 

 Eheineb. 1893, p. 102 ; Roy & Biss. Scott. Desm. 1894, p. 44 ; Borge, 

 Siissw. Chlor. Archang. 1894, p. 29 ; Nordst. Index Desm. 1896, p. 70 ; 

 West & G. S. West, Alg. S. England, 1897, p. 491 ; Schmidle, Lapp- 

 mark Susswasseralgen, 1898, p. 38 ; West & G. S. West, Alga-fl. Yorks. 

 1900, p. 70; Borg. Freshw. Alg. Faeroes, 1901, p. 226; West & G. S. 

 West, Alg. 1ST. Ireland, 1902, p. 40 ; Larsen, Freshw. Alg. E. Greenland, 



1904, p. 83 ; West & G. S. West, Freshw. Alg. Orkneys and Shetlands, 



1905, p. 18; Borge, Beitrage Alg. Schweden, 1906, p. 41. 



Euastrum (Cosmarium) decorum Gay, Monogr. loc. Conj. 1884, p. 62, 



t. 2, f. 3. 



Cosmarium decorum (Gay) De Toni, Syll. Alg. 1889, p. 968. 

 Ursinella c&lata Kiintze, Revis. gen. plant. 1891, p. 924. 

 U . decora Kuntze, 1. c. p. 924. 

 Cosmarium Westianum Benn. Freshw. Alg. S. W. Surrey, 1892, p. 11, t. 2, 



f. 14 [figure very bad]. 



Cells somewhat small, about as lono; as broad or a 



o 



little longer, deeply constricted, sinus narrowly linear 

 with a slightly dilated apex ; semicells subsemicircular, 

 margin strongly crenate, two lateral and four apical, 

 lower lateral crense larger than others and somewhat 



t ? 



flattened, crenae granulate, apical and upper lateral 

 crena3 with 2 (sometimes 3) marginal granules, lower 

 lateral crenae with 4 marginal Granules ; within the 

 margin with about three irregular series of granules 

 gradually diminishing in number away from the peri- 

 phery; lower part of semicells above the isthmus 

 furnished with a number of prominent granules, 

 covering a wide protuberance, and usually disposed in 

 rather irregular vertical series. Side view of semicell 

 broadly ovate-pyramidate, upper portions of lateral 

 margins slightly retuse, apex emarginate with rounded 

 angles. Vertical view elliptic with a broad inflation 

 at each side, slightly retuse below the poles, which are 

 rounded ; granulation of margin almost even. 



Zygospore unknown. 



Length 40-47^; breadth 36-40 /A; breadth of 

 isthmus 12-14 JJL ; thickness 24-26 /x. 



EXGLAND. Cumberland! Westmoreland! (Bissett). 

 Lancashire ! \V., X., & E. Yorks ! Leicestershire 

 (Roy). Essex! Sussex (Rolfs). Kent! Wilts! Devon! 

 Cornwall ! (Marquand). 



WALES. General ! (At 2200 ft. on Glyder Each, 

 C arnar von shire . ) 



