126 ME. W. WEST ON THE FBESHWATEE 



t37. Closteeium subtile, Breb., fornia. (PL XIX. fig. 16.) 

 A figure of a narrow form of this is given. Long. 91 fx ; lat. 



II. Cromagloun. 



1. Penium maegaeitaceum, Breb. in Ralfs, Brit. Desm. 

 p. 149, tab. 25. fig. 1. 



1. Kylemore ; Boundstone ; Ballynahinch. — II. Carrantuo- 



hill. 



Var. pihntctatum, Balfs. (Brit. Desm. p. 149.) 

 ' I. Lough Shannacloontippen. — II. Lough Griiitane. 



2. P. cylindeus, Breb. in Balfs, Brit. Desm. p. 150, tab. 25. 

 fig. 3. 



I. Kylemore ; Ballynahinch ; Rouudstone ; Lough Shanna- 

 cloontippen. 



3. P. etjeopellittjm, Roy. (Perthshire Desmids, Scot. Nat. 

 April 1877.) 



Long. 40-45 ^ ; lat. 10-12-5 p. 

 I. Kylemore. 



ft 4. P. exigtjum, nov. sp. (PI. XIX. figs. 17, 18.) 



P. parvum, cylindricum, 3-6plo longius quam latius, medio 

 fere distincte constrictum (nonnunquam non constrictum), api- 

 cibus truncatis (nonnunquam amplioribus) ; membrana delica- 

 tissime granulata, granulis irregulariter dispositis, achroa ; 

 pyrenoidibus 2-3 in utroque semicellula in serie lineari ordmatis; 

 locello subapicali corpuscula mobilia includente. 



Long. 18-5-37 fi ; lat. 6-8-5 fx. 



L Kylemore. — II. Cromagloun. 



This species differs from P. margaritaceum, Breb., and P. cyhn- 

 drus, Breb., in its smaller size, in the smaller granules which 

 are not arranged in longitudinal lines, and in its colourless 



W 



66) 



size, different form, &c. 



5. P. spieosteiolatum, Bark. (Cooke, Brit. Desm. p. 39; 

 Turner, in Journ. Boy. Micr. Soc. 1885, p. 939, tab. 16. fig. 26.) 



Long. 130-160 ji; lat. 17-20^. 



I. Ballynahinch; Lough Aunierin ; Lough Shannacloontippen ; 

 near Leenane ; near "Westport ; Boundstone.— II. Lough Gui- 



