1913] RIGG—EFFECT OF BOG WATERS 325 
and the present paper contributes the suggestion that the toxins 
act through their stunting effect on root hairs. 
The bog problem was suggested to the writer by Professor THEO- 
DORE C. FrRyYE, of the University of Wasltington, and he has had 
the advantage of his criticism and advice as well as that of Dr. 
Joun WEiNzIRL, bacteriologist in the same department. 
Summary 
1. Tradescantia grown in bog water shows stunted root hairs. 
2. Tradescantia grown in water from open lakes and springs 
immediately adjacent to bogs shows normal root hairs. 
3. Tradescantia grown in water from drained or partly drained 
bogs shows almost normal root hairs. 
4. The stunting of root hairs of Tradescantia by bog water is 
comparable with the stunting of them by exceedingly dilute solu- 
tion of sea water, of formalin, of tannic acid, of gelatin, of coffee, 
and of tea. 
5. The stunting effect of bog water on root hairs of Tradescantia 
disappears when it is diluted with an equal volume of tap water 
and in some cases when diluted with one-half its volume of tap 
water. 
6. The stunting effect of bog water on root hairs of Trades- 
cantia may be increased by boiling the water down to a fraction 
of its original volume. 
7. Many typical bog plants have no root hairs. 
8. There seems to be a toxin or toxins in bog water whose effect 
disappears with drainage of the bog. 
9. Possibly this toxin inhibits mesophytes from bogs by redu- 
cing the amount of absorptive surface exposed by the root system. 
UNIVERSITY OF WASHINGTON 
SEATTLE, WasH 
LITERATURE CITED 
1. Covitte, F. V., Experiments in blueberry culture. Bur. Pl. Ind. Bull. 
193. IgIo. 
2. DacuNowskI, A., The toxic property of bog water and bog soil. Bor. 
Gaz. 46:130-143. 1908. 
