PLATE VIII.--A, B, C, Large plants of Gemiasma verdans. A, Mature plant. B, Mature plant discharging spores and spermatia through a small opening in the cell wall. C, A plant nearly emptied. D, Gemiasma rubra; mature plant filled with microspores. E, Ripe plant discharging contents. F, Ripe plant, contents nearly discharged; a few active spermatia left behind and escaping. G, nearly empty plant. H, Vegetation in the SWEAT of ague cases during the paroxysm of sweating. I, Vegetation in the BLOOD of ague. J, Vegetation in the urine of ague during paroxysm. K, L, M, Vegetation in the urine of chronic cases of severe congestive type. N, Vegetation in BLOOD of Panama fever; white corpuscles distended with spores of Gemiasma. O, Gemiasma alba. P, Gemiasma rubra. Q, Gemiasma verdans. R, Gemiasma alba. O, P, Q, R, Found June 28,1867, in profusion between Euclid and Superior Streets, near Hudson, Cleveland, O. S, Sporangia of Protuberans.] List of objects found in the Croton water, winter of 1881 and 1882. The specimens obtained by filtering about one barrel of water: 1. Acineta tuberosa. 2. Actinophrys sol. 3. Amoeba proteus. 4. " radiosa. 5. " verrucosa. 6. Anabaina subtularia. 7. Ankistrodesmus falcatus. 8. Anurea longispinis. 9. " monostylus. 10. Anguillula fluviatilis. 11. Arcella mitrata. 12. " vulgaris. 13. Argulus. 14. Arthrodesmus convergens. 15. Arthrodesmus divergens. 16. Astrionella formosa. 17. Bacteria. 18. Bosmina. 19. Botryiococcus. 20. Branchippus stagnalis. 21. Castor. 22. Centropyxis. 23. Chetochilis. 24. Chilomonads. 25. Chlorococcus. 26. Chydorus. 27. Chytridium. 28. Clatbrocystis æruginosa. 29. Closterium lunula. 30. " didymotocum. 31. " moniliferum. 32. Coelastrum sphericum. 33. Cosmarium binoculatum. 34. Cyclops quad. 35. Cyphroderia amp. 36. Cypris tristriata. 37. Daphnia pulex. 38. Diaptomas castor. 39. " sull. 40. Diatoma vulgaris. 41. Difflugia cratera. 42. " globosa. 43. Dinobryina sertularia. 44. Dinocharis pocillum. 45. Dirt. 46. Eggs of polyp. 47. " entomostraca. 48. " plumatella. 49. " bryozoa. 50. Enchylis pupa. 51. Eosphora aurita. 52. Epithelia, animal. 53. " vegetable. 54. Euastrum. 55. Euglenia viridis. 56. Euglypha. 57. Eurycercus lamellatus. 58. Exuvia of some insect. 59. Feather barbs. 60. Floscularia. 61. Feathers of butterfly. 62. Fungu, red water. 63. Fragillaria. 64. Gemiasma verdans. 65. Gomphospheria. 66. Gonium. 67. Gromia. 68. Humus. 69. Hyalosphenia tinctad. 70. Hydra viridis. 71. Leptothrix. 72. Melosira. 73. Meresmopedia. 74. Monactina. 75. Monads. 76. Naviculæ. 77. Nitzschia. 78. Nostoc communis. 79. OEdogonium. 80. Oscillatoriaceæ. 81. Ovaries of entomostraca. 82.