Pearse—The Parasites of Lake Fishes. 
179 
Spinitectus gracilis Ward & Magath 
This is an intestinal parasite of wide distribution. Occurrence: 
Lake Geneva: pumpkinseed, bluegill, smallmouth black bass; Lake 
Pepin: bluegill, smallmouth black bass; Lake Michigan: rock bass, 
pumpkinseed. 
Acanthocephala 
Echinorhynchus coregoni Linkins 
In Lake Michigan in the intestines of long-nosed and common 
suckers, whitefish, lake trout, pickerel, five species of ciscoes, lota, 
yellow perch. 
Echinorhynchus salvelini Linkins 
In Lake Michigan in intestines of lake trout, four species of 
ciscoes, smallmouth black bass, yellow perch. 
Echinorhynchus thecatus Linton 
This was found to be a common and widely distributed intes¬ 
tinal parasite. Occurrence: Lake Geneva: rock bass, pickerel, 
bluegill, both black bass, yellow perch; Lake Mendota: rock bass, 
speckled bullhead, pumpkinseed, long-nosed gar, bluegill, both 
black bass, yellow perch; Lake Pepin: dogfish, eel, Johnny darter, 
pickerel, pumpkinseed, bluegill, both black bass, yellow perch, 
white bass, sauger; Green Lake: rock bass, speckled bullhead, 
sucker, top minnow, bluegill, both black bass, yellow perch; Lake 
Michigan: speckled bullhead, yellow perch. 
Larval individuals were found in small white crappies in Lake 
Pepin; Green Lake: pickerel, top minnow, bluegill, smallmouth 
black bass, yellow perch. 
Visceral cysts were found as follows: Lake Geneva: rock bass, 
pumpkinseed, both black bass; Lake Mendota: rock bass, speckled 
bullhead, pumpkinseed, largemouth black bass; Lake Pepin: sheeps- 
head, pumpkinseed, channel cat, largemouth black bass, tadpole 
cat; Green Lake: rock bass, speckled bullhead, pumpkinseed, top 
minnow, bluegill, largemouth black bass, yellow perch; Lake 
Michigan: speckled bullhead, sucker, yellow perch. 
