igio.] 



OX THE DISTRIBUTION OF PLANTS. 



471 



of the lake where the cat-tails occur, the following series of readings 

 are suggestive. 



28. (Position I.) Association of Typlia angiistifolia — base of 

 plant covered by water at high tide. Sp. gr. 1.0145. 



2/. (Position III.) Typlia angustifolia. Sp. gr. 1.014. 



26. (Position \ .) Typlia angustifolia. Sp. gr. 1.014. 



25. Position A'l.) Typlia angustifolia with Atriplcx hastata. 

 Submerging water with sp. gr. 1.012. 



24. (Position A'lla. ) Association of Typlia angustifolia, Atri- 

 plcx hastata, Saliconiia hcrhacca, Spavtina stricta niaritinia. Sp. 

 gr. 1.0135. 



27, (Position A'll^.) Association of Typlia angustifolia, Scirpus 

 lacustris, S. pungcns. Sp. gr. 1.0125. 



22. Outer edge of Typlia angustifolia association at the head of 

 the lake. Sp. gr. 1.0115. 



21. Head of Newberry Lake at inner edge of dense masses of 

 Typlia angustifolia with Hibiscus mosclicutos (third lot). Sp. gr. 

 1.0050. 



Influence of Saline Water on Typlia angustifolia. — Before begin- 

 ning a consideration of the data obtained by using the hydrometer 

 and thermometer combined, it is important to consider the influence 



Fig. 3. Cat-tail, Typha angustifolia. at the head of Stockton Lake near 

 Sea Girt, N. J. The tall plants are growing at Position III. 



