56 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



Page 189, add to generic description of RADIOFILUM, 

 With more or less distinct transverse lamellate or fibrillosc 

 structure. 



KKY TO TOE SPECIES OF RADIOFILUM. 



i. Cell division transverse only ; cells nniseriate. 2. 



i. Cell division transverse and longitudinal; cells uni-tuultiseriate, 



sheath often branched. 4. R. irregulare. 



2. Sheaths wide, of inner laminate and outer homogeneous layers. 



2. K. conjunctiva in. 



2. Sheath of uniform laminate structure. 3. 



3. Cells lenticular with sharp lateral edge. I. R. apicvlaluni. 



3. Cells spherical or ellipsoid. 4. 



4. Sheaths cylindrical, cells broadly ellipsoid. 3. R.Jiavcscens. 



4. Sheaths torulose, cells subspherical. 5. A', motiili/onnc. 



1. R. APICULATUM see p. 188. 



2. R. CONJUNCTIVUM Schmidle, 1894, p. 48, PI. VII, figs. 

 4-5. Filaments usually short and fragile ; cells spherical or 

 depressed-spherical, with more or less distinct and sharp lateral 

 edge, usually 6 X 4 /*, united by short gelatinous Lands, of 

 firmer consistency than the general sheath ; sheath about 25 / 

 diani., with a thin homogeneous outer layer, and an inner layer, 

 distinctly laminate transversely. Wis., G. M. Smith. Europe. 



3. R. KLAVBSCBNS G. S. West, 1899, p. 57, PI. CCCXCV, 

 figs. 10, ii. Cells broadly ellipsoid, 7.5-10.5 n diam., color yel- 

 lowish green ; sheath not much wider than cells, more or less 

 distinctly laminate. Wis., G. M. Smith; Twin Lake. Mich., 

 Transeau. Europe. 



4. R. IRRKC.UI.ARK (Wille) Bruntithaler * ; Ulothrix (/for- 

 mosfiora) irrcgularis Wille, 1880, p. 63, PI. II, figs. 41-42. 

 Cells ellipsoid, 12-15 M wide, 4-6 ft, long, dividing both laterally 

 and longitudinally ; sheath up to 30 /x wide, lamination more or 

 less distinct ; by the division of the cells the sheath may con- 

 tain two or several series, or the sheath may divide into two or 

 more series each, either reuniting to form a single sheath, or 

 forming an ordinary branch. Cuttyhunk, Mass., Miss J. M. 

 Furber ; Carp Lake, Kmmet Co., Mich., Transeau. Europe. 



5. R. MONILIPORMH Collins & Furher ms.t Cells sub- 

 spherical, sheath moniliform. following the shape of the cells. 

 Cuttyhunk, Mass., Miss J. M. Furber. 



So quoted by Heering in Pascher, 1914, p. 40, but without reference, 

 t Unpublished species; this note not a publication. 



