ae, LORANDE LOSS WOODRUFF 
one culture, developed as far as the typical proteus form (cf. 
De2o5)) 
Obviously tap water will vary from time to time throughout . 
the year, and no emphasis is placed on the completeness of the 
experiment in respect to the species which can be introduced 
through this channel. However, the work is extensive enough 
to clearly show that an insufficient number of species of Protozoa 
is introduced with ordinary tap water to make this a practical 
method for seeding infusions for study. 
H Series. The organisms which appeared in these cultures 
must have been encysted on the dry hay with which the infusions 
were made, and therefore they represent at least some of the 
forms which one may secure in the laboratory through this source. 
Hy1, Hy2, Ht1, and Ht2 showed a closely similar series of forms, 
including all those which have been noted in the previously des- 
cribed cultures except Chilomonas and typical Amoeba proteus, 
and in addition several species of Colpidium, Colpoda, Oxytricha, 
and other hypotrichous forms, Glaucoma, Holophrya, Spathidium, 
Bursaria, ete. All of these infusions were seeded with Paramae- 
cium on November 9th, and when discontinued there was a heavy 
growth of this organism in each, thus proving that a favorable 
medium was present for Paramaecium. Hy3 and Ht3, served as 
a control, and were not examined until the end of the experiments 
when they contained essentially the same forms as the other 
members of the H series. 
WH Series. This group of infusions, consisting of fresh hay 
and water partially exposed to the atmosphere, was carried as a 
control for the above experiments. The protozoan fauna which 
developed was somewhat more meager than that developed by the 
H series. The explanation of this fact is not at once apparent 
since the hay and the water employed came from the same source 
as that used in making the other infusions. It was evident that 
the cycle of the infusions of this series developed more rapidly 
than those of the other series, and a possible explanation is that 
the bacteria introduced with the water so augmented the initial 
processes of decay with their attendant phenomena that a medium 
less favorable for large growths of various protozoan forms was 
