304 Maine Agricultural Experiment Station. 1917. 



On the Differential Effect of Certain Calcium Salts 



UPON the Rate of Growth of the two Sexes of the 



Domestic Fowl.* 



Calcium Lactate and Calcium lacto-phosphate given to chicks 

 in doses of o.i gram to 0.3 grams daily are shown to increase 

 the body weight and reproductive ability of the females but in 

 no way to effect the males. An inhibitory substance, corpus 

 lutium, also inhibits this increase as the presence of the calcium 

 salts. 



A NOTE ON FITTING OF PARABOLAS.f 



Formula for the fitting of parabolas by the method of 

 Moments assuming origin at the mid-point have already been 

 given by Pearson. A need has, however, been felt by many 

 investigators for formulas and tables for fitting of parabolas 

 taking origin one unit below the first ordinate. This paper 

 supplies such a need. 



THE PROBABLE ERROR OF A MENDELIAN CLASS 

 FREOUENCY.t 



In view of the defect in the calculation of the probable 

 errors of small subclasses in mendelian work, the writer has 

 suggested a new method of estimating the significance of these 

 constants by calculating the median and quartile classes. Tested 

 on material where the hypergeometrical is known, this method 

 gives good results. 



*This paper is an abstract from a paper by Raymond Pearl, having 

 the same title and published in Science, N. S., Vol. XLIV No. 1141, pp. 

 687-688. 



tThis paper is an abstract from a paper by. John Rice Miner, having 

 the same title and published in The Proceedings of the National Academy 

 of Sciences, Vol. 3, pp. 91-95. 



$This paper is an abstract from a paper by Raymond Pearl, having 

 the same title and pubilshed in the American Naturalist, Vol. LI. No. 

 603, pp. 144-156. 



