CusHMAN: TETMEMORUS 601 
more so in the latter, about 3 times as long as wide ; apices spree! 
rounded ; cell-wall slightly punctate ; chloroplasts with I or 
pyreno oids. 
Length 65 : breadth I9 p. 
MassaAcuHusetts: Guilder Pond, on Mt. Everett, 600 meters, 
Mount Washington ! 
ey to the New England species of Tetmemoru 
Cells large, el times as long as wide; cell- wall ae or punctate in a 
definite pattern, at least near the base of the sem 
Ecilcularions or punctulations in definite iol eden lines ; cells very slightly 
attenuate from base to apex 1. 7. Brébissonii. 
Scrobiculations in horizontal oo at the base of the semicell, elsewhere scattered, 
gradually attenuate from base to apex. 2. ulatus. 
Cells smaller, less than 5 times as long as wide; celJ-wall irregularly vite 
Cells about 4 times as long as wide ; chloroplast with 3-5 pyrenoids. 
3. TZ. laevis. 
Cells about 3 times as long as wide ; chloroplasts with 1 or 2 pyrenoids. 
4. 7. minutus. 
Boston Society OF NATURAL HISTORY. 
