COSMAEIUM. 185 



175. Cosmarium Sportella Breb. 

 (PI. LXXXII, figs. 12, 13.) 



Cosmo, rium Sportella Breb. in Kiitz. Spec. Algar. 1849, p. 176 [description 

 bacT ; Liste Desm. 1856, p. 130, t. 1, f . 12 ; Arch, in Pritch. Infus. 1861, 

 p. 734 ; Kabenh. Flor. Europ. Alg. Ill, 1868, p. 169 ; Nordst. Desm. 

 Ital. 1876, p. 28 ; Nordst. in Wittr. & Nordst. Alg-. Exsic. 1877, no. 78 ; 

 fasc. 21, 1889, p. 41 ; Wolle, Desm. U. S. 1884, p. 83, t. 49, f. 28-30 

 [figures very bad] ; Cooke, Brit. Desm. 1887, p. 107, t. 41, f. 6 [figures 

 inaccurate] ; De Toni, Syll. Alg. 1889, p. 1053 ; Eoy & Biss^ Scott. 

 Desm. 1894, p. 175 ; Nordst. Index Desm. 1896, p. 240 ; West & G. S. 

 West, Alg. S. England, 1897, p. 490 ; Alga-fl. Yorks. 1900, p. 75 : Alg. 

 N. Ireland, 1902, p. 39. 



Ursinella Sportella Ktintze, Eevis. gen. plant. 1891, p. 925. 



Cells rather under medium size, slightly longer than 

 broad, very deeply constricted, sinus narrowly linear 

 with a slightly dilated extremity; semicells shortly 

 truncate-pyramidate, basal angles broadly rounded, 

 upper parts of sides just below the apex very slightly 

 (almost imperceptibly) hollowed, upper angles obtuse, 

 apex very faintly outstanding, broadly truncate and 

 straight. Cell-wall granulate, about 6-7 granules 

 visible on each lateral margin (including the basal 

 angle), upper angles strongly bigranulate (almost 

 emarginate), apex smooth or with 4-5 small marginal 

 granules, granules within the margins irregularly 

 scattered and gradually reduced in size towards the 

 centre, with a group of about 7 larger granules in the 

 centre of the semicells situated on a very slight central 

 tumour (sometimes scarcely evident and the granules 

 themselves much reduced) ; with minute punctulations 

 between the granules. Side view of semicell ovate- 

 elliptic with a rounded apex. Vertical view elliptic, 

 with an almost imperceptible 3-granulate tumour at 

 the middle on each side. Chloroplasts axile, with two 

 pyrenoids. 



Zygospore globose and furnished with spines, shortly 

 2-3-furcate at the apex and each surrounded by a 

 corona of small teeth at the base. 



Length 45-49 ^ ; breadth 42-45 ^ ; breadth of apex 

 23-25'5/x,; breadth of isthmus 13-14'5/x; thickness 

 23-24 jit ; diam. zygosp. without spines about 50 p.. 



