220 



water and were in must cases separated from the land Uy (U'cjicr water. 

 As tlie ice formed, it inishcd the i^round lii.tiiier on these shaih)\v places. 

 The ice cracks in excessively cold weather, the cracks till with water and 

 freeze ajiain. This crowds the ice and the substratum of earth still far- 

 ther shoreward. Vei'y much of tlie soutli shore of tl.e lake shows such a 

 formation. The ice-beach near the outlet of Clear Creek is at least thirty 

 inches above lake level and separates a dense swamp from the lake. In 

 this swamp thus isolated from the main lake, the semi-aquatic plants 

 readily establish themselves and thus finally reclaim the swamp land. 



The plant life in the lake is al)uudant. A bank of Scirpus practically 

 encircles the lake. Nuphar. Nymphaea. Typlia. Potamogeton, Ceratophyl- 

 lum and Chara are also abundant. The outlet is now entirely "overgrown" 

 bj- Nuphar, Nymphaea, Typha and Scirpus arranged in water zones. 



The average temperature of the water from July G to August 2.3. 1899, 

 at a depth of two feet, was 80°; the air temperature for the same time 

 was 81.5°. The deep water of the lake marked 41° and was. of course, 

 subject to no diurnal changes, nor even to any considerable seasonal vari- 

 ation. The prevailing winds during the summer months are west to 

 southwest. 



THE FISHES. 



The number of species of fishes thus far secured is forty-one. Con- 

 sidering the great varietj^ of physical conditions, the number of species is 

 small. But the number of individuals in each species is much more disap- 

 pointing. The scarcity of the larger food fishes is due to the great amount 

 of fishing in the lake. But the scarcity of the smaller fishes, the Cypri- 

 nidae. many species of the Darters, Labidesthes. etc., is not accoinited for 

 in this way. 



To show the relative numbers of a very common form which serves 

 as food for the larger species, I may take the Labidesthes sieculus. As 

 many as a gallon of this form may be secured in either Turkey Lake or 

 Tippecanoe Lake at a single haul of the seine. Not more than three or 

 four dozen were secured in Winona Lake during the entire summer. This 

 fact in itself will partially account for the scarcity of the larger food 

 fishes. The same relative proportions are true of many other forms. The 

 following list gives the species and locality from which they were se- 

 cured. The column marked (N)* gives some notion of the relative abund- 



''In some cases the number of specimens collected is marked: (+) indicates that the 

 species is abundant ; (:■), not so abundant ; ( — ), but few. 



