GONATOZYGON. 35 



5. Gonatozygon Kinahani (Arch.) Rabenh. 

 (PI. II, figs. 1-3.) 



Leptocystinema Kinahani Arch. Suppl. Cat. Desni. 1852, p. 243, 250, t. xxi, 



f. 1-4. 

 Gonatosygon Kinahani (Arch.) Eabenh. Flor. Europ. Alg. Ill, 1858, p. 156 ; 



Cooke, Brit. Desin. 1887, p. 3, t. 1, f. 3 ; West, Add. Alg. W. Yorks. II, 



1891, p. 244; West, Alg. W. Ireland, 1892, p. 114; Roy & Biss. Scott. 



Desm. 1894, p. 250. 



Cells 14-25 (sometimes 40) times longer than their 

 diameter, cylindrical ; apices truncate, sometimes very 

 slightly dilated ; cell- wall perfectly smooth. Pyre- 

 noids four to ten in each chloroplast. 



Zygospore unknown. 



Length 162-376 n ; breadth 11-14 /a. 



ENGLAND. Malham Tarn and Penyghent, W. Yorks ! 

 Strensall Common, 1ST. Yorks ! Sheep's Green, Cam- 

 bridge ! Richmond Park and Wimbledon Common, 

 Surrey ! 



SCOTLAND. Scotston Moor, Whitestripes Moor, Tilly- 

 four, Powlair, and Slewdrurn, Aberdeen ; Crathes, Kin- 

 cardine (Roy fy Bisxett). 



IRELAND. -Ballynahinch and lakes near Recess, 

 Gralway ! Churchill, Donegal ! Lough Fea, London- 

 derry ! Dublin and Wicklow (Archer). 



(Jeoyr. Distribution. Italy. Siam (var.). United 

 States. 



This species is the only Gonatozygon with a perfectly smooth 

 cell-wall. In form it is somewhat similar to G. monotaenium, 

 but is often of larger size. It is easily overlooked 011 account 

 of its apparent resemblance to sterile filaments of certain 

 species of Mougeotia. We have often obtained it in long fila- 

 ments and sometimes in almost pure gatherings. 



Genus 2. GENICULARIA De Bary, 1858. 



De Bary, Conj. 1858, p. 77. 

 Cooke, Brit. Desm. 1887, p. 184. 



Cells cylindrical, elongate, not constricted, apices 

 truncate, remaining attached in filaments for some 



