120 MB. W. WEST ON THE FRESHWATER 



Long. 440-467 fx ; lat. ad bas. semicell. 55-60 // ; lat. ad apic 

 33-35 /i. 



I. Near Westport; uear Oughterard; Lakes, Clifden to 

 Eoundstone ; Aunierin and Moher Loughs. — II. Cromagloun. 



6. Pleurotjenium rectum, Delp. {Desm. Subalp. p. 225, 

 tab. 20. figs. 8-11.) 



II. Cromagloun. 



f7. P. tridentulum, nob. [Docidiuin tridentuluui (Wolle, 

 Desm. 77. S. p. 52, pi. 10. fig. 10).] 



P. mediocre, circiter trigies longius quam latum ; semicellulse 

 modice inflatse ad basin ; gradatim attenuate ; ad apices 

 truncatae, tribus quatuorve spinis brevibus ; membrana glabra 

 [vel granulata (var. granulatum, nob.)]. 



ft Var. capitatum, nov. var. (PI. XXIV. fig. 12.) 



Yar. semicellulse granulatae, minores inflatse ad basin, apicibus 

 subcapitals et glabris, spinis brevioribus. 



Long. 495 /x ; lat. ad bas. semicell. 22 # 5 p ; lat. ad apic. 13*5 /x. 



[jffaJ. United States of America.] 



This differs from the type in its capitate apices and its shorter 

 spines. Mr. Wolle says in his short description "often granulate. ' 

 A specimen of the type seen from Harvey Lake, U.S.A., was 

 smooth and agreed with Wolle' s figure with the exception of 



having a much smaller basal inflation. 



Var. capitatum, nov. var. Forma membrana minus gran- 

 ulata. 

 I. Lakes, Clifden to Eoundstone. 



1. Closterium didymotocum, Corda. (Balfs, Brit. Desm. 



_*_ _ * ^^ ■ *. 



p. 168, tab. 28. fig. 7.) 



24-45 



1. Creggan Lough ; near Westport ; Lakes, Clifden to 

 Eoundstone ; near Ballynahinch ; Kylemore ; Eoundstone ; 

 Oorid Lough ; Lough Aunierin ; near Oughterard. — II- Car- 

 rantuohill ; Glen Caragh ; Castletown ; Sugar Loaf Mt. ; 

 Kenmare; Glengarriff ; near Lough Brin ; Upper Lake ot 

 Killarney. 



2. C. directum, Arch. (Babh. Fl. Europ. Alg. iii. P- I 27 -) 

 Long. 220-260 M ; lat. 11-125 /x ; lat. ad apic. 85 /x. 



