1902-3.] Sawdust and Fish Life. 425 



SAWDUST AND FISH LIFE. 



By a. p. Knight, M.A., M.D., Professor of Animal 

 Biology, Queen's University, Kingston. 



{Read iph February, iQOj.) 



CONTENTS. 



Part I. — Historical ............ 426 



Part II. — Experimental ........... 433 



Sinking of Sawdust 434 



Aqueous Extracts from Sawdust ......... 436 



Aeration of Water Containing Extracts 437 



Source of Extracts 437 



Wood Cells and Cell Contents 438 



Pulp Industry 439 



Beet Sugar Industry 439 



Solid Matter in Aqueous Solution Pine 440 



Solids from Cedar 440 



Effects of Cedar Sawdust Solution on Perch 441 



" " " Leech, Snail, Vorticella . 442 



" " " Worms, Tadpole .... 443 



*' " " Black Bass Fry . . . 444 



" Pine Extracts on Fish Eggs 444 



" " " Minnows, Perch, Worms, Tadpole . . 445 



" " " Crustaceans, Hydra, Vorticella, Bass. . 446 



'• Maple Extracts 448 



•' Hemlock Extracts 448 



" British Columbia Cedar Extracts 448 



" Red Pine, Oak, Elm 449 



Rapidity of Solution 449 



Fish at Mill Ends ............. 450 



A Stagnant Artificial Pool 451 



Comparative Effects of Pine, Cedar 452 



" " Hemlock Bark, Cedar Bark .... 453 



•' " Hard Wood Sawdust 454 



*' " Conclusions Based on ..... 456 



Experiments with White Pine Bark 457 



" " Hemlock and Cedar Bark 457 



Decaying Sawdust 458 



Bacteria in Wood Extracts 458 



Aromatic Compounds 459 



Nutritive Relations . 461 



Saw Mill on the Bonnechere River 462 



Conclusions. . 465. 



Acknowledgments . 465 



Dr. Connell's Bacteriological Examination 466 



NOTE. — The trees mentioned in the following report are : White Pine (Pinus Strobus, L.), Red Pine 

 (Pinus Resinosus, Ait.), British Columbia Cedar (Thuya Gig-antea, Nuttall), Ontario Cedar (Thuya Occi- 

 dentalis, Linn.), Hemlock (Thuya Canadensis, Carr.), Maple (Acer Saccharinum, Wang.), Elm (Ulmus 

 Americana Linn.), Ash (Fraxinus Sambucifolia, Lam.), Qak (Quercus Rubra, Linn), Spruce (Picea Alba, 

 Linn). 



