[Illustration: MALARIA PLANTS COLLECTED SEPT. 10, 1882, AT WASHINGTON
HEIGHTS, 176TH STREET, NEAR 10TH AVENUE, NEW YORK CITY, ETC.

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.