ILLUSTRATIONS. 



PLATE PAGE 



I. Curves of annual distribution of Oloiotrichia per square 



meter in Lake Winnebago 6 



II. Curves of annual distribution of Diaptomus sieilis and 



Diaptomus minutus per square meter in Green lake . 22 



III. Curves of annual distribution of Diaptomus oregonensis 



per square meter in Lake Winnebago .... 23 



IV. Curves of annual distribution of Epischura lacustris 



per square meter in Lake Winnebago 25 



V. Curves of annual distribution of Epischura lacustris per 



square meter in Green lake 25 



VI. Curves of annual distribution of Limnoealanus macru- 



rus per square meter in Green lake , . . 26 



VII. Curves of annual distribution of Cyclops brevispinosus 



per square meter in Lake Winnebago .... 26 

 VIII. Curves of [annual distribution of Cyclops brevispinosus 



per square meter in Green lake 26 



IX. Curves of annual distribution of Cyclops pulchellus per 



square meter in Lake Winnebago - .... 27 

 X. Curves of annual distribution of Cyclops Leuckarti per 



square meter in Green lake and Lake Winnebago . 28 



XL Curves of annual distribution of Cyclops prasinus per 



square meter in Green lake 29 



XII. Curves of annual distribution of copepod larvae per square 



meter in Green lake 29 



XIII. Curves of annual distribution of copepod larvae per square 



meter in Lake Winnebago 29 



XIV. Curves of annual distribution of Diaphanosoma bra- 



chyurum per square meter in Lake Winnebago . 31 



XV. Curves of annual distribution of Daphnia hyalina per 



square meter in Green lake 31 



XVI. Curves of annual distribution of Daphnia hyalina and 



D. retrocurva per square meter in Lake Winebago - *H 



