ILLUSTRATIONS 

 Photographs, from life, by the author 



PLATE PAGE 



I. — Winter Life in a Brook. {In color) 



Frontispiece 



II. — Slow Meadow Streams and Pond Shallows 14 



III. — Rapid Streams in Winter and Summer . 24 



IV. — Minute Plants and Animals of Pond 

 Water, (/w color. Photo, by courtesy of 

 R. W. Miner, Am. Mus. Nat. History) . 52 



V. — Pickerel- Weeds, Pontederia cordata . . 86 



VI. — Fresh Water Sponge Colonies . . .106 



VII. — Colony of Bryozoan, Plumatella; Proto- 

 zoans, Vorticella . . . . .136 



VIII. — Insect Structures; Gill of Mayfly, 



Water-Penny • . . . .184 



IX. — Wing-Pad of a Mayfly Nymph ; Air-Tubes 

 of a Dragonfly Nymph, its Respiratory 

 System . . . . . . .186 



X. — Summer Life in the Quiet Shallows of 



Ponds. (In color) .... 192 



XI. — Mayflies: Calliboetis, the Winged Insect 

 Just Emerged from Water; Blasturus, 

 Adult and its Cast Skin , . . 200 



XII. — Egg-Clusters of a Swift-Water Mayfly, 



Bcetis. ....... 202 



XIII. — Burrowing Insects, Mayfly Nymphs Ephe- 

 mera and Hexagenia and their Burrows . 206 



% XV 



