COSMAHIUM. 149 



LXXVII, fig. 13, which is a copy of Wille's original figure). 

 It differs so considerably from G. excavation in the form of its 

 semicells and in the absence of an elongated isthmus, that it 

 must necessarily be considered as a distinct species. The 

 name " Willei' could not be adopted as a specific name as 

 there is already a Cosmarium Wdlei Lagerh. (1886). 



A r ar. ordinatum West & G. S. West. (PL LXXVII, 



fig. 14.) 



Dysphinctium Willei Sckmidle, forma Schmidle, Alg. Bern. Alp. 1894, 



p. 95, t. 6, f. 2. 

 Cosi'iKi ,-^nn subexcavatum var. ordinatum West & G-. S. West, Notes Alg-. 



II, 1900, p. 293, t. 412, f . 3 ; Alga-fl. Yorks. 1900, p. 86. 



Cells a little longer than in the typical form ; semi- 

 cells broadly obovate ; granules small, disposed in 

 about 6 horizontal and 8 vertical series. 



Lenth 29-37 u breadth 17-23u; breadth of 





isthmus 1 1 5-1 3 5 /u . 



EXGLAXD.- -Ingieton, AY. Yorks ! 

 Geogr. Distribution.- -Switzerland. 



This variety occurred somewhat sparingly among mosses 

 on dripping limestone rocks. It is characterized by the 

 regular disposition of the granules and also by the distinctly 

 obovate semicells. 



149. Cosmarium orbiculatum Ealfs. 

 (PL LXXVII, figs. 15-17.) 



Cosmarium orbiculatvrn Ealfs in Ann. Mag. Xat. Hist, xiv, 1844, p. 392, 



t. 11, f. 2; Brit. Desm. 1848, p. 107, t. 17, f. 5; t, 33, f. 9; Arch, in 



Pritch. Infus. 1861, p. 734 : Babenh. Flor. Europ. Alg. Ill, 1868, p. 173; 



Nordst. Gorges Desm. 1873, p. 22 ; Kirchii. Alg. Scliles. 1878, p. 152 ; 



Wolle, Desm. U. S. 1884, p. 77, t. 14, f. 20, 21 : Cooke, Brit. Desm. 18S7. 



p. 119, t. 43, f. 1 [figures poor] ; Hansg. Prodr. Algenfl. Bolim. 1888, 



p. 249 ; De Toni, Syll. Alg. 1889, p. 962 -. Borge, Chlor. Norska Finniark. 



1892, p. 9; West," Alg. W. Ireland, 1892, p. 159; Boy & Biss. Scott. 



Desm. 1894, p. 170; Nordst. Index Desm. 1896, p. 190*; West & G. S. 



West, Alg. S. England, 1897, p. 491 ; Alga-fl. Yorks. 1900, p. 86 ; Alg. 



N. Ireland, 1902, p. 40. 



Penium orbiculaturii Kiitz. Species Alg. 1849, p. 167. 

 Tessarai'tlrra orbiculata Grim. Desm. n. Pediast. osterreicli. Moore, 1858, 



p. 493. 



Dysphiiictitnn orliiculotinn Beiiisch, Algenfl. Franken, 1867, p. 181. 

 Ursinella orlticulata Kuntze, Bevis. gen. plant. 1891, p. 925. 



Cells small, twice as long as broad, deeply con- 

 stricted, sinus widely open outwards from an acute 

 apex ; semicells circular ; cell-wall covered with sub- 



