COSMARIUM. ] 63 



157. Cosmarium Logiense Bissett. 

 (PL LXXX, figs. 1, 2.) 



Cosmarium Logiense Bissett, Desm. Windermere, 1884, p. 194, t. 5, f. 4; 

 Cooke, Brit. Desrn. 1887, p. 104, t. 41, f. 5 ; West, Alg. X. Wales, 1890, 

 p. 289 ; Alg. W. Ireland, 1892, p. 153 ; Alg. Engl. Lake Distr. 1892, 

 p. 727 ; Eoy & Biss. Scott. Desm. 1894, p. 167, t. 2, f. 15 ; Xordst. 

 Index Desm. 1896, p. 159 ; West & GK S. West, Alg. S. England, 1897 

 p. 488 ; Alga-fl. Yorks. 1900, p. 71. 



Cells of about medium size, deeply constricted, sinus 

 narrowly linear with a dilated extremity; semicells 

 reniform, with the basal angles rounded but slightly 

 subrectaiigular, dorsal region somewhat elevated, often 

 slightly flattened or even faintly retuse in the middle 

 of the apex. Side view of semicell subcircular. 

 Vertical view elliptic. Cell- wall uniformly granulate, 

 granules rather small and somewhat densely arranged 

 in obliquely decussating and vertical series, about 

 1415 oblique series and about 17 vertical series; 

 28-33 granules visible at the margin of each semicell. 

 Chloroplasts axile, each with two pyrenoids. 



Zygospore unknown. 



Length 61-65 JJL ; breadth 48-50 JJL ; breadth of isth- 

 mus 16-18 fji ; thickness 32-33 //,. 



EXIILAXD. Ano-le Tarn and Borrowdale, Cumber- 



. 



land ! Near Bowness, Westmoreland ! (Bissett). 

 Ingleton, Bowland Knotts, and Cocket Moss near 

 Giefo'leswick. AY. Yorks ! Mickle and Great Shunnor 



Oo 



Fells, N. Y r orks ! Richmond Park, Surrey ! Slap ton 

 Sands, Devon ! 



WALES.- -Near Bethesda, Bettws-y-coed, Glyder 

 Fawr (at 2,700 ft.), Llyn Cwlyd, and Y Foel Fras, 

 Carnarvonshire ! 



SCOTLAXD. Inverness, Aberdeen, Forfar, Perth!, 

 Dumbarton (Roy fy Bissett). 



IRELAXD.- -Roundstone, Galway ! Cloonee Lough, 

 Carrantuohill, and Castletown, Kerry ! 



G-eogr. Distribution.- -Q&licia> in Austria (a form). 

 W. Indies. 



C. Logiense was discovered by Bissett from the English 

 Lake District,, in which area it is more frequent than in any 



