1 68 SAUNDERS [4 4] 



Diametei iS/*, length 27^. In its measurements the Alaskan plant 

 agrees with Nordstedt's variety induratum but has the form of the type. 



Cosmarium latum Breb. (Plate XLIV, fig. 4.) 

 In a freshwater pool near Kukak Bay. 

 Diameter 68 /*, length ioo/z. 



Cosmarium contractum Kirch. (Plate XLIV, fig. 16.) 

 In freshwater near Kukak Bay. 

 Diameter 22 fi, length 22 /*. 



Cosmarium sexangulare Lund. (Plate XLIII, fig. 39.) 

 In a freshwater pond near Seldovia, Cook Inlet. 

 Diameter 27 /^, length 32 ,u. 



Cosmarium tumidum Lund. (Plate XLIV, fig. 21.) 



In a freshwater pond near Seldovia, Cook Inlet. 



Diameter 27-30 /jt, length 3538 /z. Several specimens were found, all 

 of which belong to Kirchner's variety subtile, the cytoderm being deli- 

 cately punctate over the whole surface. 



Cosmarium parvulum Brb. (Plate XLIII, fig. 6.) 

 In freshwater, Virgin Bay, Prince William Sound. 

 Diameter 17-19^, length 35-38/1. Some of the specimens have a 



smooth cytoderm and on some it is delicately punctate. 



Cosmarium kitchelii Wolle. (Plate XLIV, fig. 17.) 



In a freshwater pond Seldovia, Cook Inlet. 



Diameter 43 //., length 51^. The plant agrees in all three views 

 with Wolle's description except that the three central rows of granules 

 are neither longer nor more conspicuous than the marginal ones. 



Cosmarium pyramidatum Breb. ? (Plate XLIII, fig. 40.) 



In a freshwater pool near Juneau ; Kukak Bay. 



Diameter 35 /z, length 54 /z, isthmus n ft wide; cell membranes very 

 delicately punctate. 



Cosmarium pachydermum Lund. (Plate XLIV, fig. 12.) 

 In a freshwater pond near Seldovia, Cook Inlet. 

 Diameter 73 /z, length 103 /z. 



Cosmarium undulatum Corda. (Plate XLIV, fig. 9.) 

 In a freshwater pond near Seldovia, Cook Inlet (422). 

 Diameter 38 /z, length 59 /z; cytoderm smooth, edge crenate, ten 



crenae to a semicell ; sinus enlarged outward. 



