476 



HARSHBERGER— INFLUENCE OF SEA WATER [April 22, 



Table Showing Influence of Salinity of Water on the Dimensions of 

 Sixty Plants of Typha angustifolia. Measurements in Meters. 



Having presented the results obtained by using the hydrometer 

 without the attached thermometer, it next concerns this paper to 

 discuss and tabulate the results obtained by the hydrometer so con- 

 structed as to combine with the hydrometer scale a thermometer, 

 whereby density and temperature can be estimated at the same time. 

 This enables us then to reduce all of our specific gravity determina- 

 tions to the uniform temperature of 15° C, so that the second series 

 of observations are far more accurate as giving the actual salinity 

 of the water which bathes the roots of a number of typic salt marsh 

 plants. In all of the following data, the corrected specific gravity 

 determinations are placed within brackets. 



Observations with Hydrometer and Attached Thermometer. 



The numbered data given below were collected at three localities 

 convenient to Belmar, N. J., easily reached by trolley, viz., Manas- 

 quan Inlet, Wreck Pond and Shark River. The same plan was 

 adopted of working from the most saline conditions of environment 

 to the least saline conditions and the gradual change of the vegeta- 

 tion will be noted, if we follow the sequence of the numbered sta- 

 tions at which hydrometric readings were made. 



81. Salt water in north arm Manasquan River. Thoroughfare 

 fringed with Spartina stricta luaritiina and Saliconiia hcrbacea. Sp. 

 gr. 1.016; temp. 26°. [Sp. gr. 1.0188.] 



71. Salt Creek at bridge back of Manasquan Life Saving Station. 

 Meadow sod is here 45 chl deep, with sand below. Sp. gr. 1.0155 ; 

 temp. 23°. [Sp. gr. 1.0174.] 



