240 Proceedings of Indiana Academy of Science. 
16. Ophrydium sp. 
By far the most abundant and conspicuous protozoan in the lake was 
a species of Ophrydiuwm which formed large blue-green gelatinous colo- 
nies about the size of a hazelnut, or larger. These semitransparent 
blue-green balls remain in about the same condition the year round. 
They are found abundantly wherever the carpet Chara grows, and are 
usually attached to it or to pebbles; or, quite frequently, to mussel shells 
either alive or dead. Clear colonies, remarkable for their unusual trans- 
parency, were found on submerged pieces of tile, August and September 
(1907). At certain times, as August 1 (1906), and August 1 and 
October 12 (1907), great quantities are washed ashore. The colonies 
are sometimes hollow, as were many of those washed ashore August 1 
(1907). 
17. Hydra fusea L. 
Not frequently encountered in the lake. On October 31 (1906), 
however, multitudes were found under leaves at the water’s edge on 
the east side, and on November 13 more were found in a similar posi- 
tion. November 18 one was found attached to floating Wolffiella in 
Norris Inlet. 
THE WORMS. 
Our notes on this group are few and very unsatisfactory. We give 
here only such of them as seem to possess some value. 
The attention we were able to give to these forms was so little that 
we are unable to say much regarding their relative or actual abundance, 
their distribution, or their relation to the biology of the lake. 
Flat-worms or Planarians, small, soft, flat objects, gray above, white 
below, and oval in outline, were common on rocks and among weeds in 
the lake. In certain material (Vorticella, etc.), obtained near Norris 
Inlet, they were quite common. They were often abundant on Cerato- 
phyllum also. They were so soft that they often pulled apart when at- 
tempts were made to remove them from the rocks. 
Small pinkish parasites (probably a species of Distomum), resem- 
bling minute leeches, were found quite common in the stomachs of fishes, 
particularly the Straw Bass (Micropterus salmoides) and the Skipjack 
(Labidesthes sicculus). Usually during the winter the stomachs of 
these fishes contained little or no food, but in most cases from one to 
several of these parasites were found in each. 
Round-worms, resembling Ascaris, are frequent intestinal parasites 
of the snakes of this region, and one small form was found in the intes- 
tine of a mussel. 
Tapeworms were almost invariably present in the several shrews 
(Blarina brevicauda) examined. They were also common in the yellow 
