248 BRITISH DESMIDIACE.E. 



p. 236 ; West & G. S. West, Alg. S. England, 1897, p. 491 ; G-. S. West, 

 Alga-fl. Cambr. 1899, p. 219 ; West & G. S. West, Alga-fl. Yorks. 1900, 

 p. 85 ; Borg. Freshw. Alg. Faeroes, 1901, p. 226 ; West & Ci. S. West, 

 Alg. N. Ireland, 1902, p. 40 ; Freshw. Alg. Orkneys and Shetlands, 1905, 

 p. 22 ; Borge, Beitrage Alg. Schweden, 1906, p. 33. 



Euastrum (Cosmarium) speciosum Gay, Monogr. loc. Conj. Montpellier, 

 1884, p. 62. 



Dysphinctium notabile (Breb.) Hansg. subsp. speciosum (Lund.) Haiisg. 

 Prodr. Algenfl. Bohm. 1888, p. 290. 



D. speciosum (Lund.) Hansg. 1. c. p. 187 [in note] ; De Toni, Syll. Alg. 

 1889, p. 891 ; Schmidle, Lappmark Siisswasseralgen, 1898, p. 20. 



Cosmarium speciosum Lund, forma genuina Mask. Further Notes N. Zeal. 

 Desm. 1889, p. 16, t. 2, f. 22. 



Cells of medium size or slightly under, about 1^ 

 times as long as broad, moderately constricted, sinus 

 very narrowly linear ; semicells subrectangular, basal 

 angles scarcely rounded, very gradually attenuated 

 upwards, apical angles rounded, apex truncate, margin 

 crenate, crenations 17-19 (4 apical and about 7 

 lateral) : granulate within the margin, granules in 



/ J O O ' O 



regular radial and concentric series, 3-4 granules in 

 each radial series ; with 6-9 vertical series of granules 

 across the base just above the isthmus, 4-5 granules in 

 each series. Side view of semicell ovate-oblong, with 



o ' 



a broadly rounded apex. Vertical view elliptic, poles 

 very delicately crenulate, granules disposed in curved 

 transverse series. Chloroplasts axile, one in each 

 semicell with a central pyrenoid. 



Zygospore unknown. 



Length 54-64 //,; breadth 37-41 JJL; breadth of isthmus 

 20-26 p. ; thickness 25-28 p. 



ENGLAND.- -Westmoreland ! (Bissett). W. and N. 

 Yorks ! Epping Forest, Essex ! Chippenham Fen, 

 Cambridge! Hants (Bennett}. Near the Lizard!, 

 Cornwall (Bennett). 



WALES.- -Capel Curig, Bettws-y-Coed, Llyn Idwal, 

 Yr Orsedd, Penmaenmawr, and at 3000 ft. on 

 Snowdon, Carnarvonshire ! Ehos Gocli Bog, Eadnor- 

 shire ! 



SCOTLAND. Aberdeen !, Forfar !, Stirling (Eoy $ 

 Bissett). Skye in Inverness ! Harris, Outer Hebrides ! 

 Hoy, Orkneys ! (Also in the plankton of Loch Kir- 

 bister.) Near Scalloway, and in Bressay, Shetlands ! 



