Baker—The Fauna of The Lake Winnebago Region. 121 
most prolific; the bottom was mixed with sand and the depth of 
water and the distance from shore provided a habitat unusually 
favorable to the development of an abundant molluscan fauna. 
The associated animals were equally numerous. This station might 
equally well, perhaps, be included among the sand shore stations. 
Valvata makes up 46 per cent of the molluscan life of the gravel 
habitats. The number of species of Mollusca has increased from 
22 on the boulder shore to 35 on the gravel shore, an increase of 
63 per cent. 
Among the associated animals some of the rock-loving species 
have disappeared or become less numerous. Heptagenia and 
Psephenus are absent; Leptocella and Polycentropidae are reduced 
in numbers. Agraylea, Oecetis, and Molanna are scarce. Hemip- 
tera is represented by a few Plea striola, adult, and Belostoma 
nymphs. Among Coleoptera the larvae of an unknown Dascyllid, 
common on the boulder bottom, is rare, but Gyrinus ventralis, 
adult, is common. Of Hirudinea, Glossiphonia complanata, neph- 
eloidea and stagnalis, Expohdella punctata and Nephelopsis ob- 
scura are common. The filamentous algae harbor a number of 
species, which occur sparingly in individuals, except in the Amphi- 
pods. Planaria, a few oligochaete worms, and a number of Chiro- 
nomid larvae occupy this algal habitat. 
The groups of associated animals most numerous on the gravel 
shores of Winnebago Lake are Amphipods, forming 31 per cent, 
and Chironomid larvae, forming 41 per cent. Compared with the 
boulder shores the gravel shores have about the same average popu¬ 
lation but there is less disparity between the mollusks and asso¬ 
ciated animals in the gravel habitats (Mollusca about 40 per cent). 
Animal Life on Sand Shores (Table 1). Sand occurs on many 
parts of the shore of the lake, either in connection with gravel or 
boulders, or as large sand flats and shallows in more or less pro¬ 
tected bays. Such areas are found in Miller Bay, Asylum Bay, 
and particularly along the shore south of the mouth of Fox Eiver 
near Oshkosh, where sand borders the rocky shore for a distance of 
several miles. Fahney Bay and the bays north of Moreley and 
Black Wolf points, have sand beaches and shallows that are espe¬ 
cially well developed. South of Long Point Island sand bottom 
occurs for upwards of a mile. The shore from Fox Eiver to Stony 
Beach is perhaps characteristic of many parts of Winnebago Lake, 
This shore is bordered by boulders with some gravel. Sand begins 
