ARTIFICIAL PARTHENOGENESIS 



475 



The data for Woods Hole were put in for comparison, but with 

 no direct bearing upon the present problems. 



1 On the Gay-Lussac hydrometer scale, double glass-distilled water at 15°C. 

 giving 1000. The New Haven density was taken from water drawn from the sea 

 at Savin Rock, at the site where the Yale University Laboratory for marine work 

 is to be erected. 



2 Read off Haskell's Island on flood-tide by Prof. Loring Barrows, Department 

 Geology, Trinity College, to whom the writer is indebted for the kindness. 



' Taken at New Haven, April 27, 1912, at Harpswell, surface of open sea off 

 Haskell's Island, 16.5 at 9.00 and Woods Hole July 6, Government Wharf at the 

 U. S. B. F., at 12.00. Time data will be expressed in this paper from 1.00 to 24.00, 

 beginning at midnight. 



* Determined by titration with indicators. This, of course, gives only the 

 metal-replaceable hydrogen and not the true hydrogen ion content (see Hober '99 

 and Friedenthal '10), which can be determined by conductivity determination. 

 There is doubtless considerable difference between these two factors in sea-water 

 where sewage brings in organic matter and where the CO2 component must vary 

 widely. Unfortunately, no conductivity determinations were possible at Harps- 

 well and none have been made elsewhere. For this reason, no comparison could 

 be made unless such were the case. It may be explained that by 'alkalinity' is 

 meant the preponderance of alkali metals (Na, Mg, K, Ca) which are united to 

 CO2 and is quantitative expressed by the older method of Tornoe '76 in cubic centi- 

 meters of CO2; but compare Fox '09. 



5 Friedenthal '10, p. 546. 



^ Quoted from Loeb '09, p. 45, the determination made 'im Laboratorium,' but 

 Dr. J. F. McClendon writes me that water taken from the U. S. B. F. wharf gives 

 a faint rose color with phenolphthalein, thus making the OH content NlO^i^ or 

 even lower. 



^ McClendon, by letter. 



