SHALLOW WATER COMMUNITIES 79 
depth to 4 meters (13 ft.) Sphaerium vermontanum, which occurs rarely 
in Hickory Creek also, and midge larvae (a red and a white species) 
appear characteristic. A number of species of small fish such as the 
blunt-nosed minnow, the straw-colored minnow, and shiners are likely 
to be found in from 4-8 meters (13-26 ft.) of water. An occasional 
Lymnaea woodruffi is found at this depth. 
; REPRESENTATIVE FISHES BELONGING MAINLY TO THE TRANSITION BELT OF 
LAKE MICHIGAN (25-54 M.) 
Fic. 20.—Great Lakes trout (Cristivomer namaycush); length 3 feet (after Jordan 
and Evermann). 
Fic. 21.—The long-jaw whitefish (Argyrosomus prognathus); length 15 inches; 
from the depth of 74 meters (after Smith). 
c) Communities of protected situations (Table X).—Near Chicago, 
bays and inlets are rare. Doubtless the mouths of some of the larger 
rivers before, they were modified for navigation, were of this character. 
Such places have been studied in Lake Superior (80, 83) and the Grand 
Traverse Bay region. Out of 21 species recorded here, 16 are definitely 
