PLATE XXI. 



HYALOSPHENIA PAPILIO. 500 diameters. 



Fig. 1. Broader lateral view of an individual in the normal position, -with projected pseudopods, 

 and in the act of discharging excrementitous matter. The sarcode nearly filling the shell; the large 

 granular nucleus visible in the fundus, and contiguous to it four clear contractile vesicles. Abundant 

 form in sphagnum of most localities in the United States. Specimen from cedar swamp, Absecom, N. 

 J.. May, 1877. 



Fig. 2. Outline of the narrower lateral view of the following. 



Fig. 3. Broader lateral view of an individual with protruded pseudopods. Found with that of 

 fig.l. ^ 



Fig. 4. Individual in which the sarcode is much reduced in extent, probably from deficiency of 

 food. Three isolated green corpuscles are seen in the space between the sarcode and shell. Sphagnous 

 swamp, Tobyhanna, Pokono Mountain, July, 187(>. 



Figs. 5, 6. Two views of the same individual, with the sarcode retracted from the mouth of the 

 shell. Sphagnum, New Jersey, May 1877. 



Figs. 7,8. Two views of the same individual, with the sarcode contracted into a discoid ball. 

 Absecom, October, 1874. 



Fig. 9. Narrower lateral view of an individual with encysted sarcode, and with the mouth of the 

 shell closed by contraction and by an operculum. With the preceding. 



Fig. 10. Broad view of a similar specimen ; the mouth of the shell not closed. The sarcode 

 eucysted. The two brown balls consist of discharged excrementitous matter. Absecom swamp, Octo- 

 ber, 1874. 



Fig. 11. View of broader side of a specimen ; the mouth of the shell closed by an operculum ; the 

 sarcode encysted. Sphagnum, Swarlhmore, Delaware County, Pennsylvania, October, 1875. 



Fig. 12. View of a specimen, containing numerous green corpuscles. From sphagnum of Abse- 

 com, preserved in a glass case during the winter. The specimen observed December, 1874. Many simi- 

 lar lines observed, with variable, quantities of green corpuscles, which are suspected to be germs or 

 spores derived from the breaking up of the encysted sarcode. 



Fig. 13. Specimen of a kind repeatedly observed. Shell containing colorless granular corpuscles. 

 These occur of varied size and in variable quantity. Undetermined whether to be the spores of the 

 Hyalosphenia, or whether they are parasitic. Sphagnum, New Jersey, April, 1877. 



Figs. 14, 15. Transverse sections, exhibiting the form of the mouth, and the attachments of the 

 saicode mass to the interior of the shell. 



