PLATE XXVI. 



Figs, 1-11.— HELEOPERA PICTA. 



From the sphagnum of sphagnous swamps of New Jersey. 500 diameters. 



Fig. 1. Broader lateral view of an individual, with a profusion of pseudopods. April, 18/5. 



Fig. 2. Broader lateral view of an individual, with the sarcode forming an encysted ball, and 

 with the shell closed by a lenticular, laminated operculum. April, 1877. 



Fig. 3. Narrower lateral view of an empty shell. 



Fig. 4. Individual with the sarcode encysted, and with the mouth of the shell closed by an oper- 

 culum. April, 1877. 



Fig. 5. Another specimen in the same condition as the preceding, June, 1877. 



Figs. 6, 7. Two views of the same individual, with encysted sarcode, and mouth of the shell 

 .closed. The fundus of the shell with an accumulation of incorporated grains of sand. October, lo74. 



Figs. 8, 9. Two views of the same specimen. In tig. 8 numerous isolated green corpuscles are 

 seen, supposed to be germs derived from the breaking up of the sarcode. In fig. 9 the mouth is seen to 

 be contracted. Collected in September, 1874, and observed December 30, of the same year. 



Fig. 10. Specimen containing scattered green corpuscles or germs. Fundus of the shell with 

 incorporated sand grains. November, 1--74. 



Fig. 11. Transverse view of an empty shell showing the mouth. 



Figs. 12-20.— HELEOPEEA PETRICOLA. 



Fig. 12. Broader lateral view of an active individual, with projected pseudopods; the fundus of 

 the shell loaded with an accumulation of large grains of sand. H.imrnonton pond, New Jersey, Septem- 

 ber, 1877. 333 diameters. 



Fig. 13. Broader lateral view of an individual with encysted sarcode, and with the mouth of the 

 shell closed by an operculum. Fig. 14. Narrower lateral view of the same, in outline. Sphagnum, 

 Eongacoming, N. J., September, 1875. 500 diameters. 



Fig. 15. Empty shell, with conical fundus; broader lateral view. Absecom, N. J., September, 

 1875. 250 +. 



Figs. 16, 17. Two views of an empty shell. Absecom pond, N. J. 200 -j-. 



Fig. 18. Broader lateral view of an empty shell. Fig. 19. Transverse section of the same, with 

 the mouth. Sphagnum, Absecom, N. J. 200 +. 



Fig. 20. Empty shell thickly incorporated with fragments of diatoms and sand. Absecom pond, 

 N. J. 250 +. 



Figs. 21-24.— NEBELA CAUDATA. 



Sphagnum of Absecom, N. J. 500 diameters. 



Fig. 21. Broader lateral view of an empty shell. June, 1877. 



Fig. 22. Individual in which the shell appeared to be composed of chitinoid membrane, with cir- 

 cular disks. The sarcode encysted, and the mouth of the shell closed by a thick laminated operculum. 

 September, 1874. 



Figs. 23, 24. Two views of the same individual, with encysted sarcode, and mouth of the shell 

 closed. The shell was of chitinoid membrane of obscure structure. April, 1876. 



