Feb., 1907.] 
Notes on a Sandusky Bay Shrimp. 
75 
latter were found in greatest abundance two or three hundred 
feet from shore where the water was three or four feet deep. 
(The coves of Sandusky Bay are as a rule quite shallow). Tow¬ 
ing near the surface was unsuccessful, a few were secured at the 
bottom, but most were taken midway, and somewhat nearer the 
bottom. 
The most abundant vegetation in the coves of Sandusky 
Bay is included in the following list: 
Mvriophvllum spicatum L. (Very abundant). 
Vallisneria spiralis L. (Very abundant.) 
Ceratophvllum demersum L. (Abundant.) 
Naias flexilis (Willd.) Rost & Schmidt. (Abundant.) 
Philotria canadensis (Mx) Britt. (Water Weed.) (Very 
abundant.) 
Potamogeton perfoliatus L. (Common; also five or six other 
species). 
Pontederia cordata L. (Pickerel weed.) 
Zizania aquatica L. (Wild Rice.) 
Scirpus lacustris L. (Great Bulrush.) 
Nvmphaea advena Soland. 
Castalia tuberosa (Paine) Greene. 
Nelumbo lutea (Willd.) Pers. 
Light Experiments. 
On Aug. 17, 1906, thirteen shrimps were taken and at once 
placed in an aquarium two thirds full of water with a few pond- 
weeds and sand on the bottom. The aquarium was then taken 
into the dark room. Ten minutes after this it was examined 
with an acetylene gas lantern and the shrimps were found scat¬ 
tered. Holding the lamp for a moment- at one end there was 
an immediate response, many swimming toward the light. The 
shrimps were then left in the dark for an hour. 
2:46 P. M. Shrimps scattered. Within one minute five re¬ 
sponded to the light, coming to the glass. (Light left in position). 
2:55 P. M. Ten were at the light end, one within four inches 
and two at the farthest end. The movement toward the light 
was not a darting, but a gliding motion. When the glass was 
reached the motion was continued from side to side, but in one 
or two minutes the shrimps came to rest. 
3:09 P. M. All seemed to be in about the same position. 
4:15 P. M. The remaining shrimps were nearer the light. 
The light end of the aquarium at this time was fairly plastered 
with pond-snails which happened to be in the aquarium, eleven 
out of a possible fourteen had crawled up the glass. 
4:45 P. M. Only two shrimps remained at the darker end. 
6:00 P. M. The shrimps were pretty well scattered again. 
Those that could be observed had their heads turned away from 
