354 TUFTS COLLEGE STUDIES, VOL. II, No. 3 



slightly clavate, in the main branches 2-6 diam. long, 45-55 p- 

 diam.; in the ramuli 4-10 diam. long, 30-40 ^ diam. Europe. 

 Both the type of this species and the var. Flotowiana are given 

 by Wolle, 1887, p. 126, as occurring "in stagnant water" and 

 it is quite probable that this species occurs here, though no cer- 

 tain specimens have been seen. Tilden, American Algae, No. 

 29, in the specimen examined is quite insufficient and unde- 

 terminable. The label'gives the diam. of the main cells as 75 /x, 

 of the branches as 43 ^ ; considerably above the figures given by 

 Wolle or Kirchner. No. 30 of the same distribution is labelled 

 C. oligodona Kg. var. flotowiana (Kg.) Hansg. Prodr. Si, and 

 the filaments are stated to be 15 /A diam.; an examination of the 

 specimen shows that they are really 60 ^u. diam. in the main 

 branches. Hansgirg gives dimensions for the same 40-56 /j.. 

 The confusion is such that no conclusion can be drawn from 

 Miss Tilden's specimens or Wolle's descriptions and figures. 



49. C. CRISPATA (Roth) Kiitzing, 1843, p. 264; Wolle, 

 1887, p. 126. Forming loose masses ; main filaments sparingly 

 branched laterally or dichotomously ; branching above alternate, 

 more dense, and filaments more slender in each order of 

 branches ; main filaments 40-75 /x diam., in some varieties some- 

 what more; in ramuli 20-35 P- '> ce ^ s cylindrical, 5-20 diam. 

 long, usually proportionally longer in the ramuli than in the 

 main filaments ; ramuli not tapering, rounded at the end ; cell 

 wall thin and delicate. 



The very long, slender filaments with erect branches gradu- 

 ally decreasing in size, with long, delicate cells, make this a 

 fairly distinct species. Many varieties have been described, 

 but they are rather vague in their distinctions. 



Forma VITREA (Kiitz.) Rabenhorst, 1868, p. 336 ; Algen, No. 

 1529 ; Kiitzing, 1854, PI. XL,, fig. i. A delicate pale form, with 

 long cells ; Iowa. The plant distributed under this name in 

 Tilden, American Algae, No. 277, seems to be rather C. Kuetz-. 

 ingiana Rab. 



As No. 2570, Rabenhorst, Algen, is distributed under the 

 name of C. crispata Roth h. virescens Forma thcrmalis Briigg., a 

 plant from Bethlehem, Pa., rather shorter-jointed than usual for 

 this species. 



As P. B.-A., No. 1193, is distributed a very long and spar- 

 ingly branched plant from California, under the name of C. cris- 



