CYUXDKnCYSTlS. 01 



//. Cells very slightly constricted. 



4. Cylindrocystis diplospora Lund. 

 (PI. IV, figs. 40, 41.) 



Cylindrocystis diplo^mra Lund. Desm. Suec. 1871, p. 83, t. 5, f. 7; Coi .>!<. 

 'Brit Dcsm. ISMi, p. 46, t. 18, f. 1; Roy & Biss. Scott, Desm. IS'.M, 



p. (52 (sep.) ; West & G. S. West, Alg. S. England, 1897, p. 478 ; Alg;i-n. 



Yorks. 1900, p. 44 ; Alg. N. Ireland, 1902, p. 20. 

 Penium diplosporwm Jacobs. Desm. Dauem. 1875, p. 164. 

 ? Schizospora pachyli ///'' Eeinsch, Coutrib. Alg. et Fung. 1875, p. 87, 



t. 17, f. 1. 

 Calocylindrus diplosporus Wolle, in Bull. Torr. Bot. Club. 1882, p. 15 ; 



Desm. U.S. 1884, p. 56, t. 12, f. 18. 



Cells moderately large, twice longer than their dia- 

 meter, subcylindrical, slightly constricted in the middle, 

 gradually but faintly dilated towards the apices which 

 are truncately rounded ; cell-wall slightly thickened at 

 the apex, smooth and colourless ; chloroplasts with 

 numerous radiating processes. 



Zygospore dou.Ui.', compressed, transversely suit- 

 rectangular with the external angles rounded. 



Length 52'5-66ju; breadth 22'5-oo^t; breadth of 

 zygosp. 06 m length of halt zygosp. 38-42 /u. 



ENGLAND. Cumberland ! Westmoreland! (lliwtt). 

 W. and N. Yorks ! Lancashire ! Essex ! Surrey ! 

 Hants! Devon (Bennett). Cornwall! (Baun'tt). 



\Y.\Li:s. Capel Curig, Llyn Idwal, and Bethesda, 

 Carnarvonshire ! Ffestiniog, Merioneth ! 



SCOTLAND. Sutherland!, Ross!, Inverness!, Aber- 

 deen, Kincardine, Perth ! , Argyll ; often conjugated 

 (Roy fy B'issett). Orkneys ! Outer Hebrides ! 



IRELAND. -- Galway ! Kerry! Wicklow (Air her). 

 Donegal ! Londonderry ! Antrim ! Down ! 



Geogr. Distrilmfion. Germany. Xor\vay. Sweden, 

 Denmark. Lapland in Russia. Greenland. India. 

 New Zealand. East Africa (var.). United States. 



Var. major West. (PI. IV, figs. 42, 43.) 



C diplospora var. major West, Alg. W. Ireland, 1892, p. 131, t. 20, f. 3 ; 

 West & G. S. West, New Brit. Freshw. Alg. ls92, p. 4,t. l,f. !) ; Alga-fl. 

 Yorks. 1900, p. 44 (forma constricta) ; Eoy & Biss. Scott. Desm. 1MH, 

 p. 62 (sep.). 



