142 MR. G. H. WATLES ON FRESHWATER RHIZOPODA 



DislrihutJon. Colorado (35) : Mcassachusetts (17) ; New Hampshire (19) ; 

 New Jersey ! (30) ; New York ! (20) ; Pennsylvania (30) ; British Columbia 

 (39); Alaska. 



Var. IRREGULARIS, Penavd. (PI. 12. fig. 20.) 



Less common than type and below the normal size. 

 Length 140 [jl or under. 



Var. CURVATA, var. nov. (PI. 12. fig. 21.) 



Test as in the type, but curved as in Ci/pJwderia ; aperture polygonal, 

 formed by 6-7 plates. 



Leno-th 80-100 fi ; breadth 33-45 fi ; aperture 11-16 fx ; thickness 

 25-28 /J,. 



Distribution. Penney's Pond, Good Gronnd. 



Several living, but no active individuals were seen ; the amount of curva- 

 ture of the test is subject to variation. 



[Cockerell (12, 1911) records this genus as Quadrvlella, the name 

 Quadrula being preoccupied in another Philum.] 



Genus Heleopera, Leidij. 

 Heleopera nodosa, sp. nov. (PI. 12. figs. 22-24.) 



Heleopera 2yetricoln pars, Leid3% pi. 20. figs. 12, lo, 20. 



Test large, elongate, slighf-ly compressed, the ratio of the transverse axes 

 being about 3:4; a[)ex acute, terminated by a nodular mass of large quartz- 

 orains ; aperture bordered by slightly recurved lips ; plasma and pseudopodia 

 normal. 



Lengtli 152-213 /x; breadth 80-94 fx \ thickness 60-75 fx; aperture 

 45-60 /A in width. 



Hahitat. Submerged sphagnum. 



Distribution. Lakehurst, New Jersey. 



Leidy (fig. 12) illustrates an individual of this species broader in propor- 

 tion to its length than any of those found at Lakehurst. //. nodosa is 

 distinguished from //. petricola by its greater size, its elongate form, the 

 acute apex bearing a nodular mass of sand-grains, and its less compression ; 

 it bears no resemblance to any other species of Heleopera. At Lakehurst, 

 N.J., it is not uncommon. 



H. spnAGNi {Leidif), Hopk. (10). 



Difflugia {Nebela) sphagni, Leidy (1874) (31). 

 Heleopera picta, Leidy (1879) (30), pi. 26. figs. 1-li, 



